Patent Publication Number: US-10782421-B2

Title: Photonic calorimeter and process for performing calorimetry

Description:
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
     This invention was made with United States Government support from the National Institute of Standards and Technology (NIST), an agency of the United States Department of Commerce. The Government has certain rights in the invention. Licensing inquiries may be directed to the Technology Partnerships Office, NIST, Gaithersburg, Md., 20899; voice (301) 301-975-2573; email tpo@nist.gov; reference NIST Docket Number 17-025US1. 
    
    
     BRIEF DESCRIPTION 
     Disclosed is a photonic dosimeter to accrue cumulative dose, the photonic dosimeter comprising: a substrate; a waveguide disposed on the substrate and that: receives a primary input light; transmits secondary input light from the primary input light to a dosimatrix; receives a secondary output light from the dosimatrix; and produces primary output light from the secondary output light; the dosimatrix disposed on the substrate and in optical communication with the waveguide and that: receives the secondary input light from the waveguide; produces the secondary output light that is communicated to the waveguide; and comprises an active element that undergoes conversion from a prime state to a dosed state in response to receipt, by the active element, of a dose of radiation; and a cover layer disposed on waveguide and the dosimatrix. 
     A process for performing dosimetry with the photonic dosimeter, the process comprising: receiving, by the waveguide, primary input light; producing, by the waveguide, secondary input light from the primary input light; receiving, by the dosimatrix, the secondary input light from the waveguide; producing, by the dosimatrix, secondary output light from the secondary input light; receiving, by the waveguide, the secondary output light from the dosimatrix; producing, by the waveguide, primary output light from the secondary output light; subjecting the dosimatrix to ionizing radiation; and changing the active element from the prime state to the dosed state in response to receiving ionizing radiation by the dosimatrix to perform dosimetry. 
     A photonic calorimeter for converting ionizing radiation dose to heat, the photonic calorimeter comprising: a radiation absorber comprising a radiation absorber and a radiation absorber disposed in the radiation absorber and bounded by the radiation absorber such that the radiation absorber: receives ionizing radiation; and converts the ionizing radiation into heat; a temperature compensator disposed within the radiation absorber and comprising: a compensation waveguide disposed in optical communication with a compensation resonator and that: receives primary compensation input light; communicates a resonant frequency based on the primary compensation input light to the compensation resonator; receives secondary compensation output light from the compensation resonator; and transmits primary compensation output light that is based on the secondary compensation output light; and a compensation resonator disposed in optical communication with the compensation waveguide and that: comprises an optical resonance; receives, from the compensation waveguide, the resonant frequency corresponding to the optical resonance; and produces the secondary compensation output light in response to receipt of the resonant frequency; a thermal isolator on which the radiation absorber is disposed and that thermally isolates the radiation absorber from heat loss by thermal transfer due to physical contact by an object, and the temperature compensator changes the optical resonance of the compensation resonator in response to a change in temperature of the radiation absorber due to absorption of the ionizing radiation by the radiation absorber. 
     A process for performing calorimetry with the photonic calorimeter, the process comprising: receiving, by the compensation waveguide, primary compensation input light; producing, by the compensation waveguide, resonant frequency from the primary compensation input light; receiving, by the compensation resonator, the resonant frequency from the compensation waveguide; producing, by the compensation resonator, secondary compensation output light from the resonant frequency; receiving, by the compensation waveguide, the secondary compensation output light from the compensation resonator; producing, by the compensation waveguide, primary compensation output light from the secondary compensation output light; subjecting the radiation absorber to ionizing radiation; producing, by radiation absorber, heat from the ionizing radiation; communicating the heat to the compensation resonator; and changing the optical resonance of the compensation resonator in response to producing heat from the ionizing radiation by the ionizing radiation to perform calorimetry. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following description should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike. 
         FIG. 1  shows a plan view of a photonic dosimeter; 
         FIG. 2  shows a cross-section along line A-A of the photonic dosimeter shown in  FIG. 1 ; 
         FIG. 3  shows a plan view of a photonic dosimeter; 
         FIG. 4  shows a cross-section along line A-A of the photonic dosimeter shown in  FIG. 3 ; 
         FIG. 5  shows a plan view of a photonic dosimeter; 
         FIG. 6  shows a cross-section along line A-A of the photonic dosimeter shown in  FIG. 5 ; 
         FIG. 7  shows a plan view of a photonic dosimeter; 
         FIG. 8  shows a cross-section along line A-A of the photonic dosimeter shown in  FIG. 7 ; 
         FIG. 9  shows a perspective view of a photonic dosimeter includes a plurality of waveguides and dosimatrixes; 
         FIG. 10  shows a plan view of the photonic dosimeter shown in  FIG. 9 ; 
         FIG. 11  shows a perspective view of a photonic dosimeter includes a plurality of waveguides and dosimatrixes; 
         FIG. 12  shows a plan view of the photonic dosimeter shown in  FIG. 11 ; 
         FIG. 13  shows a photonic calorimeter; 
         FIG. 14  shows a cross-section along line A-A of the photonic calorimeter shown in  FIG. 13   
         FIG. 15  shows a perspective view of a photonic calorimeter includes a plurality of temperature compensators; 
         FIG. 16  shows an array of photonic dosimeters subjected to ionizing radiation; 
         FIG. 17  shows a photonic calorimeter subjected to ionizing radiation; 
         FIG. 18  shows a thermometer in panels A, B, and C; 
         FIG. 19  shows a thermometer including a heater disposed on a substrate in panels A, B, and C; 
         FIG. 20  shows a thermometer including a heater disposed in a substrate in panels A, B, and C; 
         FIG. 21  shows a thermometer including a heater disposed on an optical resonator in panels A, B, and C; 
         FIG. 22  shows a thermometer in panels A, B, and C; 
         FIG. 23  shows a thermometer including an optical resonator having a conical shape in panels A, B, and C; 
         FIG. 24  shows a thermometer including a waveguide having a plurality of apertures in panels A, B, and C; 
         FIG. 25  shows a thermometer including an aperture; 
         FIG. 26  shows a thermometer including a plurality of waveguides in panels A, B, and C; 
         FIG. 27  shows a thermometer including an optical resonator having a Bragg grating in panels A, B, C, and D; 
         FIG. 28  shows a thermometer including a plurality of optical resonators and a plurality of waveguides in panels A, B, and C; 
         FIG. 29  shows a thermometer including a waveguide in panels A and B; 
         FIG. 30  shows a waveguide including a Bragg grating in panels A, B, and C; 
         FIG. 31  shows a waveguide including an end coupler; 
         FIG. 32  shows a graph of transmission versus wavelength for a plurality of temperatures; 
         FIG. 33  shows a graph of intensity versus temperature in panel A and a graph of resonant wavelength versus temperature in panel B; 
         FIG. 34  shows a thermometer system in panel A and a thermometer system in panel B; 
         FIG. 35  shows a thermometer system in panel A and a system to detect temperature of an article in panel B; 
         FIG. 36  shows a graph of state versus cumulative dose in panel A and a graph of state versus cumulative dose in panel B; 
         FIG. 37  shows a graph of photonic calorimeter output versus amount of ionizing radiation; 
         FIG. 38  a graph of transmission versus frequency prior to subjecting a photonic dosimeter to ionizing radiation in panel A and after subjecting the photonic dosimeter to ionizing radiation in panel A; 
         FIG. 39  shows a micrograph of a thermometer; 
         FIG. 40  shows a graph of transmission versus wavelength at a plurality of temperatures in panel A and a graph of normalized transmission versus wavelength at a plurality of temperatures in panel B; 
         FIG. 41  shows a graph of wavelength versus temperature in panel A and a graph of wavelength versus temperature in panel B; 
         FIG. 42  shows a graph of wavelength versus dose; 
         FIG. 43  shows a graph of wavelength versus temperature; 
         FIG. 44  shows a graph of power versus wavelength; 
         FIG. 45  shows a graph of Q and change in wavelength versus date; 
         FIG. 46  shows a graph of residual and peak wavelength versus temperature; 
         FIG. 47  shows cross-sections of pedestal and chip; and 
         FIG. 48  shows a graph of positions for a gamma-ray field. 
     
    
    
     DETAILED DESCRIPTION 
     A detailed description of one or more embodiments is presented herein by way of exemplification and not limitation. 
     The National Institute of Standards and Technology (NIST) uses water calorimetry as a primary standard for absorbed dose for which the SI unit is the gray (Gy), wherein a radioactive cobalt-60 (Co-60) source irradiates a volume of water, and the energy received is calculated from the rise in water temperature as measured by immersed thermistors to determine an estimated depth-dose profile. However, there is an urgent and growing interest in making dosimetry measurement at a smaller scale than provided by this primary standard. To this point, no conventional method directly measures radiation dose in such dimensions, and this capability is needed for medical and industrial applications such as microbeam therapy, microelectronics, and cellular dosimetry. 
     The NIST on a Chip (NOAC) program is researching a solution based on silicon chip fabrication and telecommunications technology. The goal is micro-scale calorimetry with photonic thermometers that are in the form of a fiber Bragg grating or silicon ring resonators embedded in a radiation-resistant substrate. These could be arranged to perform real-time dose measurements in a phantom, and eventually even in vivo. 
     Described here is a photonic dosimeter and photonic calorimeter that overcome limitations of conventional devices and provide photonic dosimetry and photon calorimetry that expand uses of photonic dosimetry and calorimetry. It is contemplated that arrays of miniaturized sensors of the photonic dosimeter and photonic calorimeter are multiplexed in an array separately or together on a chip measure radiation. These chips can be arranged to determine perform real-time absorbed-dose levels in a phantom and provide dosage tailored sensors for individual patients. 
     The photonic dosimeter and photonic calorimeter herein provide increased sensitivity, spatial resolution, optical readout, and multiplexing in devices. The photonic dosimeter and photonic calorimeter reduce dependence on Co-60 sources, include new portable sensors, and provide measurement articles for quantitative nuclear medicine. The photonic dosimeter and photonic calorimeter independently provide response of thousands of photonic thermometers through a single fiber optic interface. NIST research into fabricating the photonic dosimeter and photonic calorimeter shown that the photonic dosimeter and photonic calorimeter withstand exposure to ionizing radiation so that the photonic dosimeter and photonic calorimeter can be used harsh environments, such as space or energy-generation. Although a more detailed discussion follows, the photonic dosimeter and photonic calorimeter can be a silicon photonic device that can be irradiated with up 1 MGy of gamma radiation and 250 kGy of beta radiation, which is 10,000 times higher than medical radiation treatment levels, with little to no damage to the photonic devices and provide baseline drift in individual exposure over time that is negligible. 
     The photonic dosimeter and photonic calorimeter can include a photonic thermometer that is highly sensitive and resistant to change in response due to a physical impact. Moreover, the thermometer is useful as self-calibrating or self-diagnosing thermometer. The thermometer has an integrated optical resonator with a resonant frequency that changes with temperature due to thermal expansion or a thermo-optic effect of the optical resonator. The thermometer can include a thermal member to provide a selected temperature change to the optical resonator. Advantageously, the thermometer is to calibrate or determine a performance of an article, e.g., remotely. Further, the thermometer has a robust physical construction and is small, yet scalable. The thermometer also is rugged, does not require frequent, expensive, time-consuming re-calibration, and has a small thermal mass that does not rely upon voltage measurement for temperature determination. The thermometer can be fabricated in bulk quantities in a mass production environment. Beneficially, the thermometer involved temperature dependent light transmission and is resistant to electromagnetic interference. Additionally, the thermometer is deployable in harsh environments and supplants calibration of on-board temperature sensors. 
     In an embodiment, with reference to  FIG. 1  and  FIG. 2 , photonic dosimeter  200  accrues cumulative dose and includes substrate  210 ; waveguide  212  disposed on substrate  210 . Waveguide  212  receives primary input light  214 , transmits secondary input light  218  from primary input light  214  to dosimatrix  220 ; receives secondary output light  216  from dosimatrix  220 , and produces primary output light  222  from secondary output light  216 . Photonic dosimeter  200  also includes dosimatrix  220  disposed on substrate  210  and in optical communication with waveguide  212 . Dosimatrix  220  receives secondary input light  218  from waveguide  212  and produces secondary output light  216  that is communicated to waveguide  212 . Dosimatrix  220  includes active element  224  that undergoes conversion from prime state  230  to dosed state  232  in response to receipt, by active element  224 , of a dose of radiation from being subjected to ionizing radiation  254 ; and cover layer  228  disposed on waveguide  212  and dosimatrix  220 . In an embodiment, light member  248  includes light source  250  that provides primary input light  214  to waveguide  212  and light detector  252  that receives primary output light  222  from waveguide  212 . Communication of primary input light  214  or primary output light  222  between light member  248  and waveguide  212  can be propagation through free space or propagation through a condensed optical medium such as a fiber optic cable, wherein a first fiber optical cable can interconnect light source  250  to waveguide  212 , and a second fiber optical cable can interconnect light detector  252  to waveguide  212 . It should be appreciated that communication of secondary input light  218  from waveguide  212  to dosimatrix  220  and that communication of secondary output light  216  from dosimatrix  220  to waveguide  212  is due to evanescent coupling between waveguide  212  and dosimatrix  220  in a presence of light, e.g., primary input light  214  in waveguide  212 . 
     In an embodiment, with reference to  FIG. 3  and  FIG. 4 , photonic dosimeter  200  includes cover layer  228  disposed on dosimatrix  220  such that dosimatrix  220  and waveguide  212  are interposed between substrate  210  and cover layer  228 . 
     In an embodiment, with reference to  FIG. 5  and  FIG. 6 , photonic dosimeter  200  includes cladding  226  disposed on dosimatrix  220  such that dosimatrix  220  is interposed between substrate  210  and cladding  226 , and cladding  226  is interposed between dosimatrix  220  and cover layer  228 . 
     In an embodiment, with reference to  FIG. 7  and  FIG. 8 , photonic dosimeter  200  includes temperature compensator  234  disposed on substrate  210 . Temperature compensator  234  compensates for a temperature change of photonic dosimeter  200  as a function of time during which active element  224  accrues cumulative dose and undergoes conversion from prime state  230  to dosed state  232  in response to receipt, by active element  224 , of the dose of radiation from ionizing radiation  254 . Temperature compensator  234  includes compensation waveguide  238  disposed on substrate  210  proximate to compensation resonator  236 . Compensation waveguide  238  receives primary compensation input light  242 , communicates resonant frequency  240  based on primary compensation input light  242  to compensation resonator  236 , receives secondary compensation output light  244  from compensation resonator  236 , and transmits primary compensation output light  246  that is based on secondary compensation output light  244 . Temperature compensator  234  includes compensation resonator  236  disposed on substrate  210  proximate to compensation waveguide  238  and dosimatrix  220  such that compensation resonator  236  and compensation waveguide  238  are in optical communication via evanescent coupling. Compensation resonator  236  has an optical resonance and receives, from compensation waveguide  238 , resonant frequency  240  corresponding to the optical resonance and produces secondary compensation output light  244  in response to receipt of resonant frequency  240 . Temperature compensator  234  changes the optical resonance of compensation resonator  236  in response to a change in temperature of dosimatrix  220 . 
     In an embodiment, light member  256  includes light detector  260  that provides primary compensation input light  242  to compensation waveguide  238  and light source  258  that receives primary compensation output light  246  from compensation waveguide  238 . Communication of primary compensation input light  242  or primary compensation output light  246  between light member  256  and compensation waveguide  238  can be propagation through free space or propagation through a condensed optical medium such as a fiber optic cable, wherein a first fiber optical cable can interconnect light detector  260  to compensation waveguide  238 , and a second fiber optical cable can interconnect light source  258  to compensation waveguide  238 . It should be appreciated that communication of resonant frequency  240  from compensation waveguide  238  to compensation resonator  236  and that communication of secondary compensation output light  244  from compensation resonator  236  to compensation waveguide  238  is due to evanescent coupling between compensation waveguide  238  and compensation resonator  236  in a presence of light, e.g., primary compensation input light  242  in compensation waveguide  238 . 
     In an embodiment, with reference to  FIG. 9  and  FIG. 10 , photonic dosimeter array  400  includes a plurality of photonic dosimeter  200  (e.g.,  200 A,  200 B, . . . ,  200 N, wherein N is an integer number of photonic dosimeters  200  that can be, e.g., thousands of photonic dosimeters  200 ) and optionally temperature compensator  234 . In an embodiment, photonic dosimeters  200  are laterally disposed on substrate  210  as shown in  FIG. 9  and  FIG. 10 . In an embodiment, photonic dosimeters  200  are stackedly disposed on substrate  210  as shown in  FIG. 11  and  FIG. 12 . Moreover, individual photonic dosimeters  200  (e.g.,  200 A,  200 B, . . . ,  200 N) independently can be addressed and optically communicate with light members  248 . 
     While photonic dosimeter  200  accrues cumulative dose from ionizing radiation  254  for performing dosimetry, photonic calorimeter  300  converts a dose of ionizing radiation  254  to heat for performing calorimetry. In an embodiment, with reference to  FIG. 13  and  FIG. 14 , photonic calorimeter  300  includes radiation absorber  268  that has outer surface  264  and interior material  266  disposed in interior material  266  and bounded by outer surface  264 . Radiation absorber  268  receives ionizing radiation  254  and converts ionizing radiation  254  into heat. Photonic calorimeter  300  also includes temperature compensator  234  disposed within radiation absorber  268 . Temperature compensator  234  includes compensation waveguide  238  disposed in optical communication with compensation resonator  236 . Compensation waveguide  238  receives primary compensation input light  242 , communicates resonant frequency  240  based on primary compensation input light  242  to compensation resonator  236 , receives secondary compensation output light  244  from compensation resonator  236 , and transmits primary compensation output light  246  that is based on secondary compensation output light  244 . Compensation resonator  236  is disposed in optical communication with compensation waveguide  238  and includes an optical resonance and receives, from compensation waveguide  238 , resonant frequency  240  corresponding to the optical resonance and produces secondary compensation output light  244  in response to receipt of resonant frequency  240 . Thermal isolator  262  on which radiation absorber  268  is disposed thermally isolates radiation absorber  268  from heat loss by thermal transfer due to physical contact by an object. Here, temperature compensator  234  changes the optical resonance of compensation resonator  236  in response to a change in temperature of radiation absorber  268  due to absorption of ionizing radiation  254  by radiation absorber  268 . 
     In an embodiment, photonic calorimeter  300  further includes substrate  210  on which thermal isolator  262  is disposed. In this configuration, thermal isolator  262  is interposed between substrate  210  and radiation absorber  268 , and radiation absorber  268  is thermally isolated from substrate  210  by thermal isolator  262 . 
     In an embodiment, with reference to  FIG. 15 , photonic calorimetric array  402  includes a plurality of photonic calorimeter  300 , e.g.,  300 A,  300 B, . . . ,  300 N, wherein N is an integer number of photonic calorimeters  300  that can be, e.g., thousands of photonic calorimeters  300 . In an embodiment, photonic calorimeters  300  are laterally disposed on thermal isolator  262  as shown in  FIG. 15 . In an embodiment, photonic calorimeters  300  are stackedly disposed on thermal isolator  262 . Moreover, individual photonic calorimeter  300 , e.g.,  300 A,  300 B, . . . ,  300 N, independently can be addressed and optically communicate with light members  256 . 
     In an embodiment, with reference to  FIG. 16 , photonic dosimeter array  400  is subjected to ionizing radiation  254  from radiation source  404 . Sensing elements can be 10 micrometers to 100 micrometers length, 500 nanometers to 1000 nanometers width, and 200 nanometers to 500 nanometers depth; the sensing element can be disposed proximate to a waveguide to which it evanescently couples, with a gap separating the two elements of 100 nm to 900 nm; sensing elements are separated by at least 1 micrometer. Accordingly, photonic dosimeter array  400  can be subjected to ionizing radiation  254  in vitro. In some embodiments, photonic dosimeter array  400  is implanted in head  406  of a person, wherein photonic dosimeter array  400  is subjected to ionizing radiation  254  in vivo. In an embodiment, with reference to  FIG. 17 , photonic calorimeter  300  is subjected to ionizing radiation  254  from radiation source  404 , wherein radiation absorber  268  absorbs ionizing radiation  254  and converts ionizing radiation  254  to heat that changes the optical resonance of individual photonic calorimeter  300 , e.g.,  300 A,  300 B, . . . ,  300 N, in photonic calorimetric array  402 , wherein an amount of change depends upon a position of the photonic calorimeter  300 , e.g.,  300 A,  300 B, . . . ,  300 N, relative to the an incident position of photonic calorimeter  300 , e.g.,  300 A,  300 B, . . . ,  300 N, in the array as irradiated by ionizing radiation  254 . In this manner, photonic dosimeter array  400  or photonic calorimetric array  402  are position sensitive detectors with respect to a position of incidence of ionizing radiation  254  on photonic dosimeter array  400  or photonic calorimetric array  402 . 
     With reference to  FIG. 18A  (top view of temperature compensator  234 , also referred to as thermometer herein, e.g., thermometer  332  and the like),  FIG. 18B  (cross-section along line A-A of  FIG. 18A ), and  FIG. 18C  (cross-section along line B-B in  FIG. 18A ), in an embodiment, temperature compensator  234  includes compensation resonator  236  (also referred to herein as optical resonator, e.g., optical resonator  328 , that can be, e.g., a ring resonator) disposed on substrate  210 . Compensation waveguide  238  (also referred to herein as waveguide, e.g., waveguide  334 ) is disposed on substrate  210  proximate to compensation resonator  236 . Compensation resonator  236  has an optical resonance and is configured to receive resonant frequency  240  corresponding to the optical resonance. Compensation waveguide  238  is configured to receive primary compensation input light  242  (also referred to herein as input light), to communicate the resonant frequency  240  to compensation resonator  236 , and to transmit primary compensation output light  246  (also referred to herein as output light). Temperature compensator  234  is configured to change the optical resonance in response to a change in temperature of compensation resonator  236 . Distance D separates compensation resonator  236  and compensation waveguide  238 . Compensation resonator  236  has outer diameter OD, inner diameter ID, thickness H 1 , and width W 1 . Compensation waveguide  238  has thickness H 2  and width W 2 . 
     According to an embodiment shown in  FIG. 19A  (top view of temperature compensator  234 ),  FIG. 19B  (cross-section along line A-A of  FIG. 19A ), and  FIG. 19C  (cross-section along line B-B in  FIG. 19A ), temperature compensator  234  includes thermal member  314  disposed on substrate  210  opposing compensation resonator  236 . According to an embodiment shown in  FIG. 20A  (top view of temperature compensator  234 ),  FIG. 20B  (cross-section along line A-A of  FIG. 20A ), and  FIG. 20C  (cross-section along line B-B in  FIG. 20A ), temperature compensator  234  includes thermal member  314  disposed in substrate  210  opposing compensation resonator  236 . Thermal member  314  is configured to change or maintain a temperature of compensation resonator  236 . In some embodiments, thermal member  314  increases a temperature of compensation resonator  236 . In an embodiment, thermal member  314  decreases a temperature of compensation resonator  236 . 
     With reference to  FIG. 20B , over layer  315  can be interposed between thermal member  314  and compensation resonator  236 . Over layer  315  can be made of a same or different material as substrate  210 . In an embodiment, over layer  315  includes a material that efficiently communicates thermal energy between thermal member  314  and compensation resonator  236 . 
     According to an embodiment shown in  FIG. 21A  (top view of temperature compensator  234 ),  FIG. 21B  (cross-section along line A-A of  FIG. 21A ), and  FIG. 21C  (cross-section along line B-B in  FIG. 21A ), temperature compensator  234  includes thermal member  314  disposed on compensation resonator  236  opposing substrate  210 . An over layer (e.g.,  315 , not shown) can be interposed between compensation resonator  236  and thermal member  314 . 
     Besides ring resonator indicated as compensation resonator  236 , various other optical resonators can be used in the thermometer. In an embodiment, as shown in  FIG. 22A  (top view of temperature compensator  234 ),  FIG. 22B  (cross-section along line A-A of  FIG. 22A ), and  FIG. 22C  (cross-section along line B-B in  FIG. 22A ), temperature compensator  234  includes first intermediate member  321  interposed between disk resonator  316  and substrate  210 . Additionally, second intermediate member  322  is interposed between compensation waveguide  238  and substrate  210 . Although first intermediate member  321  and second intermediate member  322  are shown as having a frustoconical shape, first intermediate member  321  and second intermediate member  322  can have any shape (e.g., cylindrical, square, rectangular, ellipsoidal, parallelpiped, and the like) effective to separate substrate  210  from disk resonator  316  or compensation waveguide  238 . 
     In one embodiment, as shown in  FIG. 23A  (top view of temperature compensator  234 ),  FIG. 23B  (cross-section along line A-A of  FIG. 23A ), and  FIG. 23C  (cross-section along line B-B in  FIG. 23A ), temperature compensator  234  includes concave resonator  317  disposed on substrate  210 . Concave resonator  317  includes base  319  proximately disposed to substrate  210 , concave portion  318 , and protuberance  320 . Concave portion  318  has width W 3  and depth H 4 , and protuberance  320  has width W 4  at a top surface thereof. Thickness H 3  is a thickness of concave resonator  317 . Width W 4  of protuberance  320  optionally can be absent in some embodiments. 
     According to an embodiment, as shown in  FIG. 24A  (top view of temperature compensator  234 ),  FIG. 24B  (cross-section along line A-A of  FIG. 24A ), and  FIG. 24C  (cross-section along line B-B in  FIG. 24A ), temperature compensator  234  includes compensation waveguide  238  having an aperture  324  disposed therein. In some embodiments, a plurality of apertures  324  is distributed along a length axis of compensation waveguide  238 . In certain embodiments, the plurality of apertures  324  have a diameter of the same size. In an embodiment, some of the plurality of apertures  324  have different size diameters. According to one embodiment, the plurality of apertures  324  have different size diameters such that apertures  324  are arranged symmetrically with respect to compensation resonator  236  with largest diameter apertures  324  located distal to compensation resonator  236  and smallest diameter apertures  324  located proximate to compensation resonator  236 . 
     In an embodiment, as shown in  FIG. 25A  (top view of temperature compensator  234 ),  FIG. 25B  (cross-section along line A-A of  FIG. 25A ), and  FIG. 25C  (cross-section along line B-B in  FIG. 25A ), temperature compensator  234  includes aperture  325  interposed between compensation resonator  236  and substrate  210 . Aperture  325  has a size in a dimension (e.g., depth, width, or height) effective to mechanically or optically decouple compensation resonator  236  and substrate  210  such that compensation resonator  236  and substrate  210  independently support a mechanical mode or an optical mode. In this manner, without wishing to be bound by theory, it is believed that a mechanical mode or an optical mode of compensation resonator  236  is not quenched by substrate  4 . 
     According to an embodiment, as shown in  FIG. 26A  (top view of temperature compensator  234 ),  FIG. 26B  (cross-section along line A-A of  FIG. 26A ), and  FIG. 26C  (cross-section along line B-B in  FIG. 26A ), temperature compensator  234  includes auxiliary waveguide  326  disposed on substrate  210  opposing compensation waveguide  238 , wherein compensation resonator  236  is interposed between compensation waveguide  238  and auxiliary waveguide  326 . Accordingly, temperature compensator  234  includes a drop-add arrangement of compensation resonator  236 . 
     In an embodiment, as shown in  FIG. 27A  (top view of temperature compensator  234 ),  FIG. 27B  (cross-section along line A 1 -A 1  of  FIG. 27A ), and  FIG. 27C  (cross-section along line B-B in  FIG. 27A ), temperature compensator  234  includes optical resonator  328  (e.g., a ring resonator as shown) disposed on substrate  210  proximate to compensation waveguide  238 . Optical resonator  328  includes a Bragg grating  327  integrally disposed in optical resonator  328 . Bragg grating  327  includes a plurality of regions having a different refractive index from each, e.g., alternating first region  329  (having a first index of refraction) and second region  330  (having a second refractive index). The first or second index of refraction can be the same or different as an index of refraction of a remainder of material of optical resonator  328 . 
     According to an embodiment, Bragg grating  327  is a periodic (as shown in  FIG. 27D , which is a cross-section along line A 2 -A 2  of  FIG. 27A ) or aperiodic perturbation of an effective index of refraction in optical resonator  328 . In an embodiment, the perturbation causes reflection of light (propagating in optical resonator  328 ) for a wavelength of light that satisfies a Bragg condition. Light at other wavelengths that does not satisfy the Bragg condition is substantially unaffected by Bragg grating  327 . 
     In some embodiments, as shown in  FIG. 28A  (top view of temperature compensator  234 ),  FIG. 28B  (cross-section along line A-A of  FIG. 28A ), and  FIG. 28C  (cross-section along line B-B in  FIG. 28A ), temperature compensator  234  includes auxiliary optical resonator  331  (e.g., a ring resonator as shown) disposed on substrate  210  proximate to auxiliary waveguide  326  and spaced apart therefrom by distance D 2 . Distance D 3  separates auxiliary optical resonator  331  and compensation resonator  236 . Although, two optical resonators ( 236 ,  331 ) are shown, some embodiments include a plurality of optical resonators coupled and interposed between compensation waveguide  238  and auxiliary waveguide  326 . In one embodiment, the plurality of optical resonators includes different types for optical resonators, e.g., a ring resonator, disk resonator, concave resonator, or a combination thereof. Such combination of coupled optical resonators ( 236 ,  331 ) provide a narrow bandwidth of frequencies communicated to auxiliary waveguide  326  from a broader band of frequencies transmitted by compensation waveguide  238  via optical resonators ( 236 ,  331 ). 
     According to an embodiment, as shown in  FIG. 29A  (top view of thermometer  332 ) and  FIG. 29B  (cross-section along line A-A of  FIG. 29A ), thermometer  332  includes waveguide  334  disposed on substrate  333 . Aperture  335  is present in substrate  333  and is interposed between a portion of waveguide  334  and substrate  333 . Aperture  335  has width W and thickness H, a dimension of each of which independently can be varied during formation to form various shapes (e.g., circular, square, polygonal, and the like) and aspect ratios of length L, width W, and thickness H. In some embodiments, waveguide  334  includes a Bragg grating  327  (see  FIG. 27C ) in a position proximate to aperture  335 . 
     In some embodiments, the thermometer includes the substrate and the waveguide disposed on the substrate to receive input light and to transmit output light such that the aperture is interposed between the substrate and the waveguide. The waveguide is configured to change an intensity of the output light at a wavelength in response to a change of a temperature of the waveguide. 
     In an embodiment, the thermometer includes a substrate; an optical resonator disposed on the substrate and including an optical resonance. The optical resonator is configured to receive the resonant frequency corresponding to the optical resonance. The thermometer also includes a waveguide disposed on the substrate proximate to the optical resonator to receive input light, to communicate the resonant frequency to the optical resonator, and to transmit output light with an aperture is interposed between the substrate and the optical resonator, the substrate and the waveguide, or a combination comprising at least one of the foregoing. Further, the thermometer is configured to change the optical resonance in response to a change in temperature of the optical resonator. 
     In some embodiments, the optical resonator includes a ring resonator, a concave disk resonator, a photonic waveguide, disk resonator, a microsphere resonator, a photonic crystal cavity, a photonic array, or a combination comprising at least one of the foregoing. As such, the optical resonator can be a ring, disk, or spherical structure disposed at a selected distance from a waveguide. A radius of the optical resonator is selected so an effective length of a circumference is an integer of a resonant wavelength. In some embodiments, the optical resonator is the ring resonator that has a substantially uniform width with respect to a radial dimension of the ring resonator, e.g., substantially uniform width W 1  between outer diameter OD and inner diameter ID as in  FIG. 18C . 
     According to an embodiment, input light is coupled into the thermometer from a light source, coupled from the thermometer to a detector, or a combination thereof. In an embodiment, the waveguide comprises a Bragg coupler, an end coupler, or a combination comprising at least one of the foregoing disposed at a terminus of the waveguide. As shown in  FIG. 30A  (top view of compensation waveguide  238 ) or  FIG. 30B  (cross-section along line A-A of  FIG. 30A ), compensation waveguide  238  includes Bragg coupler  336  disposed at a terminus thereof. Bragg coupler  336  includes a plurality of protrusions  337  and depressions  338  alternatingly disposed on substrate  210 . With reference to  FIG. 30C  (an alternate embodiment for a Bragg coupler corresponding to a cross-section along line B-B in  FIG. 30A ), depressions  338  are blind with respect to substrate  210  relative to through features as shown in  FIG. 30B . In one embodiment, depressions  338  include blind depressions  338 , through depressions, or a combination thereof. Here, “through” refers to expose substrate  210  through depressions  338 , and “blind” refers to covering substrate  210  by depressions  338  such that substrate  210  is not exposed. It is contemplated that a Bragg coupler uses a grating structure (e.g., protrusions  337  and depressions  338 ) to couple input light into the thermometer and to couple output light out of the thermometer. In an embodiment, coupling light by compensation waveguide  238  is evanescent coupling via Bragg coupler  336 . 
     In an embodiment, as shown in  FIG. 31 , compensation waveguide  238  includes edge coupler  339  disposed at a terminus of compensation waveguide  238 . Edge coupler  339  couples light in and out by, e.g., a pigtailed fiber optic, which is connected, e.g., adhered, to substrate  210 . 
     Temperature compensator  234  includes substrate  210 . Substrate can include any material that can effectively be processed (e.g., micromachined, including lithography and the like) to form a support structure for optical resonator (e.g.,  236 ), thermal member  314 , waveguide (e.g.,  238 ), or other components thereof. 
     In a particular embodiment, substrate  210  includes a semiconductor. An exemplary semiconductor is an element from group 11, 12, 13, 14, 15, or 16 (IUPAC nomenclature, which respectively is identical to group I, II, III, IV, V, or VI) of the periodic table such as a Si, Ga, Ge, As, In, Sn, Sb, Te, At, Hf, Zn, and the like, or a combination thereof. According to an embodiment, substrate  210  is a compound semiconductor such as SiC, SiGe, GaN; a group 13-15 (also referred to as a group III-V) semiconductor such as AlSb, AlAs, Aln, AlP, BN, GaSb, GaAs, GaN, GaP, InSb, InAs, InN, InP, and the like; a group 12-16 (group II-VI) semiconductor such as CdSe, CdS, CdTe, ZnO, ZnSe, ZnS, ZnTe, and the like; a group 11-17 (group I-VII) semiconductor such as CuCl and the like; a group 14-16 (group IV-VI) semiconductor such as PbS, PbTe SnS, and the like; a layer semiconductor such as PbI 2 , MoS 2 , GaSe, and the like; an oxide semiconductor such as CuO, Cu 2 O, and the like; (Al,Ga)N, (Al,Ga)As, (In,Ga)As, (Al,Ga)Sb, (In,Ga)Sb, as well as nitride, arsenide, antimonide quaternary III-V alloys, or a combination comprising at least one of the foregoing. Examples of II-VI alloys include, but are not limited to CdSe, CdTe, CdS, ZnSe, and combinations thereof. Examples of Group III-V ternary alloys include, but are not limited to, (Ga,Al)As, (In,Ga)As, and combinations thereof. Exemplary Group III-V quaternary alloys include (Ga,In)(As,P), (In,Al,Ga)Sb, and the like. Exemplary Group III-nitride alloys include (Ga,Al)N, (Ga,In)N, (Al,In)N, (Ga,Al,In)N, and combinations thereof. Quaternary alloys of the above may also be employed. 
     Substrate  210  also can include a supplemental element such as C, H, N, Li, Na, K, Mg, Ca, Sr, Ba, Bi, B, Al, P, S, O, and the like in an amount typically less than an amount of the semiconductor. In an embodiment, substrate  210  includes silicon, and the silicon is optionally doped. According to an embodiment, the semiconductor is an intrinsic semiconductor or an extrinsic semiconductor doped with a selected dopant, e.g., a p-dopant or an n-dopant. In one embodiment, the substrate includes a p-dopant. In another embodiment, substrate  210  includes an n-dopant. In a particular embodiment, substrate  210  is p-doped Si. In one embodiment, substrate  210  is n-doped Si. Substrate  210  can be produced from, e.g., commercially available semiconductor grade p-doped Si having a particular crystalline orientation, e.g., having Miller indices &lt;111&gt;, &lt;100&gt;, and the like. Substrate  210  can be amorphous, polycrystalline, or a single crystal. In an embodiment, substrate  210  has a stacked structure that includes a plurality of semiconductor layers such as by forming films as SiGe/Si/SiGe/Si on a Si substrate. In some embodiments, substrate  210  includes crystalline domains among amorphous material. 
     In another embodiment, substrate  210  includes a glass, Pyrex, sapphire, polymer, ceramic, or an electrically conductive material, e.g., a metal. The substrate can be electrically conductive, semiconductive, or electrically insulating. 
     A thermal conductance of substrate  210  can be selected by choice of a composition of substrate  210  as well as a geometrical shape or size of substrate  210 . 
     A dielectric layer can be disposed on substrate  210  to generally isolate substrate  6  from, e.g., contamination or deterioration during formation of compensation resonator  236 . In an embodiment, the dielectric layer electrically insulates substrate  210  from thermal member  314 . The dielectric layer can include an oxide of an element in substrate  210  or independently can be an oxide of a semiconductor material such as SiO 2 . According to an embodiment, the dielectric layer is an oxide such as an oxide that includes an element from substrate  210 , e.g., an oxide of the semiconductor (also referred to herein as a semiconductor oxide). In an embodiment, substrate  210  includes Si, and dielectric layer  323  includes silicon dioxide (SiO 2 ). Additional dielectric layer materials include gallium oxide (GaO 3 ), aluminum oxide (Al 2 O 3 ), or alloys thereof, oxides of compounds from Groups III and V or alloys thereof, and the like. Exemplary oxides in the dielectric layer also include ZnO, HfO 2 , SnO 2 , In 2 O 3 , Zn 2 SnO 4 , Ga 2 O 3 , Al 2 O 3 , and the like. In an embodiment, the dielectric layer is a product of oxidation of a portion of substrate  210  to produce the semiconductor oxide. According to one embodiment, the oxide is a product of rapid thermal oxidation of substrate  210  so that the oxide (the dielectric layer) is derived from substrate  210 . In another embodiment, the oxide is a product of low temperature oxidation of substrate  210  to produce an oxide. In a further embodiment, the oxide is a product of depositing the oxide on substrate  210 , which may or may not involve oxidation of substrate  210 . In a certain embodiment, the dielectric layer includes SiO 2  as the oxide, which is a product of oxidation of substrate  210  that includes Si. In some embodiments, the dielectric layer includes a semiconductor oxide, a ceramic (e.g., ZrO 2 , Al 2 O 3 , SiC, Si 3 N 4 , BN, BaTiO 3 , and the like), a glass, a polymer, or a combination thereof. In some embodiments, the dielectric layer includes an organic compound such as a polymer, e.g., cellulose, poly(methyl methacrylate), and the like. 
     Substrate  333  can have the same composition, properties and function as substrate  210 . 
     Photonic dosimeter  200  accrues cumulative dose for performing dosimetry, and photonic calorimeter  300  converting ionizing radiation dose to heat for performing calorimetry. Photonic dosimeter  200  includes waveguide  212 . In an embodiment, waveguide  212  guides light along a path; can have dimensions from 300 nm to 1 micrometer width, 200 nm to 500 nm height; can include silicon and similar material; and can be operable at a wavelength from 1 micron to 2.5 microns. The waveguide can contain a coupling element to communicate light into the waveguide. Exemplary coupling elements include a Bragg coupler, inverse taper, and the like. The waveguide can include an optical resonator to measure temperature, strain, or radiation dose. 
     Compensation waveguide  238  guides light along a path; has dimensions of: 300 nm to 1 micrometer width, 200 nm to 500 nm height; is composed primarily of materials like silicon and works over the range of 1 micron to 2.5 microns wavelength of light; the waveguide may contain coupling elements to bring light into the waveguide, such as Bragg couplers or inverse tapers; the waveguide may include optical resonators to enable measurement of temperature. 
     Aperture  324  has a diameter from 25 nm to 500 nm, more specifically 50 nm to 300 nm, in compensation waveguide  238 . In an embodiment, a plurality of apertures  324  have different size diameters. According to one embodiment, the plurality of apertures  324  have different size diameters such that apertures  324  are arranged symmetrically with respect to compensation resonator  236  with largest diameter apertures  324  located distal to compensation resonator  236  and smallest diameter apertures  324  located proximate to compensation resonator  236 . 
     Aperture  325  is an opening interposed between compensation resonator  236  and substrate  210 . Aperture  325  has a size in a dimension (e.g., depth, width, or height) effective to mechanically or optically decouple compensation resonator  236  and substrate  210  such that compensation resonator  236  and substrate  210  independently support a mechanical mode or an optical mode. 
     Auxiliary waveguide  326  is similar in construction and function to the compensation waveguide  238 . In a particular embodiment, auxiliary waveguide  326  transmits light from the compensation resonator  236  to light detector  260 . 
     Waveguide  334  is similar in construction and function to compensation waveguide  238 . 
     Aperture  335  is an opening interposed between a portion of waveguide  334  and substrate  333 . Aperture  335  has width W and thickness H, a dimension of each of which independently can be varied during formation to form various shapes (e.g., circular, square, polygonal, and the like) and aspect ratios of length L, width W, and thickness H. 
     Edge coupler  339  is disposed at the terminus of a waveguide. Edge coupler  339  couples light in and out of a waveguide, in a particular embodiment by, e.g., a pigtailed fiber optic, which is connected, e.g., adhered, to substrate  333 , brings light into and out of a compensation waveguide  238 . 
     Waveguide  366  is a waveguide that transmits light to (or receives light from) an optical resonator (e.g. optical ring resonator  367 ). Waveguide  366  has similar construction and function to compensation waveguide  238 . 
     In photonic dosimeter  200 , dosimatrix  220  is an array of photonic resonators that changes resonant frequency in response to received dose. Photonic dosimeter  200  includes active element  224 . Active element  224  interacts with ionizing radiation  254 , whereupon active element  224  undergoes conversion from prime state  230  to dosed state  232  in response to receipt, by active element  224 , of a dose of ionizing radiation  254 . Active element  224  can include a compound semiconductor that is a group III-V semiconductor. Exemplary group III-V semiconductors include AlN, GaN, InN, TlN, BP, AlP, GaP, InP, TlP, BAs, AlAs, GaAs, InAs, TlAs, BSb, AlSb, GaSb, InSb, TlSb, BBi, AlBi, GaBi, InBi, TlBi, or a combination thereof. It is contemplated that besides active element  224 , dosimatrix  220  can include materials mentioned above in addition to silicon dioxide, III-V materials coated in silver, titanium, gold or copper and polymers synthesized using free-radical polymerization. In an embodiment, dosimatrix  220  consists essentially of active element  224 . 
     To determine accrued dose of ionizing radiation  254  by active element  224 , active element  224  undergoes conversion from prime state  230  to dosed state  232 . Exemplary conversions include frequency change, changes in linewidth or intensity. In undergoing conversion from prime state  230  to dosed state  232 , active element  224  experiences a change in refractive index brought on by changes in temperature, stress, chemical or physical characteristics such as density or volume/geometry resulting in frequency change. In undergoing conversion from prime state  230  to dosed state  232 , resulting in changes in linewidth or intensity, active element  224  experiences changes in light transmission, reflectivity that results in increased optical losses resulting in lower quality factors or greater linewidths. Accordingly, prime state  230  can be the frequency, linewidth or intensity of the resonance before dosing. Further, dosed state  232  can be the frequency, linewidth or intensity of the resonance after dosing. 
     In an embodiment, compensation resonator  236  comprises an element from group I of the periodic table (IUPAC group 11), group II of the periodic table (IUPAC group 12), group III of the periodic table (IUPAC group 13), group IV of the periodic table (IUPAC group 14), group V of the periodic table (IUPAC group 15), or group VI of the periodic table (IUPAC group 16) in an absence of a compound semiconductor that includes a group III-V semiconductor. 
     Disk resonator  316  is an optical resonator that can include materials such as those in optical resonators  328  or compensation waveguide  238 . In a particular embodiment, a disk resonator consists of a circular structure with radius R, thickness T, sitting on a pedestal  321  composed of substrate  210 . 
     Concave resonator  317  includes a base  319  proximately disposed to substrate  210 , concave portion  318 , and protuberance  320 . Concave portion  318  has width W 3  and depth H 4 , and protuberance  320  has width W 4  at a top surface thereof. Thickness H 3  is a thickness of concave resonator  317 . Width W 4  of protuberance  320  optionally can be absent in some embodiments. 
     Bragg grating  327  includes a plurality of regions having a different refractive index from each. The first or second index of refraction can be the same or different as an index of refraction of a remainder of material of optical resonator  328 . According to an embodiment, Bragg grating  327  is a periodic or aperiodic perturbation of an effective index of refraction in optical resonator  328 . In an embodiment, the perturbation causes reflection of light (propagating in optical resonator  328 ) for a wavelength of light that satisfies a Bragg condition. Light at other wavelengths that does not satisfy the Bragg condition is substantially unaffected by Bragg grating  327 . 
     Bragg coupler  336  an end coupler, or a combination comprising at least one of the foregoing disposed at a terminus of the waveguide. As shown in  FIG. 31A  (top view of waveguide  238 ) or  31 B (cross-section along line B-B of  FIG. 30A ), waveguide  238  includes Bragg coupler  336  disposed at a terminus thereof. Bragg coupler  336  includes a plurality of protrusions  337  and depressions  338  alternatingly disposed on substrate  210 . With reference to  FIG. 30C  (an alternate embodiment for a Bragg coupler corresponding to a cross-section along line B-B in  FIG. 30A ), depressions  338  are blind with respect to substrate  210  relative to through features as shown in  FIG. 30B . In one embodiment, depressions  338  include blind depressions, through depressions, or a combination thereof. Here, “through” refers to expose substrate  210  through depressions  338 , and “blind” refers to covering substrate  210  by depressions  338  such that substrate  210  is not exposed. It is contemplated that a Bragg coupler uses a grating structure (e.g., protrusions  337  and depressions  338 ) to couple input light into and output light out of the optical resonator, e.g. optical resonator  328 . In an embodiment, coupling light by waveguide  238  is free-space coupling via Bragg coupler  336 . 
     Ring resonator  367  is an optical resonator that includes a ring structure having a 10 μm radius and is separated from waveguide  366  by 130 nm. The ring resonator has a free spectral range of 9.2 nm at 1550 nm, Q-factor of 52000, and estimated group index of 4.2. 
     The optical resonator and waveguide independently can be made from a same or different material as the substrate. In some embodiments, the optical resonator incudes sapphire, silicon, silica, silicon nitride, aluminum nitride, diamond, silicon carbide or a combination thereof. The material for forming the optical resonator can be selected based on a resonant wavelength for the optical resonator, e.g., silicon for devices a resonant frequency in a near infrared region (e.g., up to 2 μm wavelength), silicon nitride or aluminum nitride for a visible wavelength, sapphire for a terahertz wavelength, and the like. 
     Cladding  226  includes a dielectric material disposed on photonic elements, such as a waveguide (e.g. waveguide  212 ) or dosimatrix  220 . In an embodiment, cladding  226  is interposed between the dosimatrix  220  and the cover layer  228 . In an embodiment, the dielectric layer electrically insulates substrate  210  from thermal member  314 . The dielectric layer can include an oxide of an element in substrate  210  or independently can be an oxide of a semiconductor material such as SiO 2 . According to an embodiment, the dielectric layer is an oxide such as an oxide that includes an element from substrate  210 , e.g., an oxide of the semiconductor (also referred to herein as a semiconductor oxide). 
     Cover layer  228  can include a material to undergo a thermophysical or chemical change (e.g. strain, temperature, density, volume, conductivity, dielectric constant) or alters the ionizing radiation  254 . In an embodiment, cover layer  228  communicates or enhances changes to dosimatrix  220  that influence the change from prime state to dose state in dosimatrix  220 . In an embodiment, cover layer  228  is composed of polymers (e.g., free-radical polymerization products), water, graphite, SiO 2 , diamond, SiN, air, Si, and the like. 
     Thermal isolator  262  thermally isolates radiation absorbers (e.g., radiation absorber  268 ) from heat loss or gain by thermal transfer due to physical contact by an object (e.g., substrate  210 ). Thermal isolator  262  can include material with low thermal conductivity, e.g., air, vacuum, or a mechanical element that can include a standoff made of structured materials or partial removal of a substrate, such as substrate  210 . 
     In photonic calorimeter  300 , radiation absorber  268  absorbs ionizing radiation  254  and converts ionizing radiation  254  to secondary radiation that is absorbed, thermalized, and conducted as heat to the compensating resonator  236 . Radiation absorber  268  includes outer surface  264  and interior material  266  disposed in and bounded by outer surface  264 . Interior material  266  can be a solid, fluid, or combination thereof. When interior material  266  includes a fluid, the fluid is contained inside outer surface  264  that is a solid material that entraps the fluid to prevent the fluid from loss out of radiation absorber  268 . When interior material  266  is a solid, outer surface  264  can be a same solid as interior material  266  or a different solid than interior material  266 . Interior material  266  absorbs ionizing radiation  254  and converts ionizing radiation  254  to heat. outer surface  264  can be transparent to ionizing radiation  254  or can absorb and convert to heat ionizing radiation  254 . Exemplary fluids include water, fluoropolymers, blood, blood plasma, alcohols, oils, water, and the like. Exemplary solids include graphite, silicon, silica, sapphire, alanine, diamond, polymers (such as polymethylmethacrylate, polyvinyl alcohol, polydimethylsiloxane), hydroxyapatite, and graphite, and the like. 
     Thermal member  314  measures temperature. In various embodiments, thermal member  314  includes a metal layer. The metal layer can be disposed on substrate  210 , on the dielectric layer, or disposed on substrate  210  and covered by a dielectric layer interposed between thermal member  314  and compensation resonator  236 . Exemplary conductive materials include a metal such as a transition metal, alkaline earth metal, alkali metal, rare earth metal, metal carbide, metal oxide, metal sulfide, or a combination thereof. Exemplary metals include Zr, Hf, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Ta, W, Re, Os, Ir, Pt, Au, Li, Na, K, Be, Mg, Ca, Sr, Ba, Gd, and the like. Thermal member  314  can include the metal layer, a non-metal (e.g., graphene, carbon nanotubes, carbon black, and the like), or a combination thereof. 
     Cover layer  315  is made of material(s) that may undergo a thermophysical and/or chemical change (e.g. strain, temperature, density, volume, conductivity, dielectric constant) or alters the ionizing radiation  254  and, in an embodiment, communicates and/or enhances changes to the dosimatrix  220  that influence the change from prime state to dose state in the dosimatrix  220 . In an embodiment, cover layer  315  is composed of polymers (e.g. free-radical polymerization products), water, graphite, SiO 2 , diamond, SiN, air, Si. 
     Intermediate members ( 321 ,  322 ) can include materials described for the substrate, waveguide, or a combination thereof. Dielectric layer  323  includes a dielectric material that provides dielectric separation of elements disposed on dielectric layer  323 . 
     Ionizing radiation  254  is radiation that can include x-rays, gamma rays, or particles. In some embodiments, ionization radiation includes electrons, alpha particles, positrons, or protons that cause ionization when the ionization radiation interacts with a material. Radiation source  404  is a material that produces ionizing radiation  254 , e.g., radioactive material such as Co-60 or an accelerator-based source. 
     Light member  248  contains a light source and a light detector. In an embodiment, it contains light source  250  and light detector  252 . Light member  256  contains a light source and a light detector. In an embodiment, it contains light source  260  and light detector  258 . Light source  250  is a source of light. In an embodiment, light source  250  is a laser. Light source  258  is a source of light. In an embodiment, light source  258  is a laser. Light source  341  is a source of light. In an embodiment, light source  341  is a laser. First light source  347  is a source of light. In an embodiment, light source  347  is a laser. Second light source  348  is a source of light. In an embodiment, light source  348  is a laser. Light source  354  is a source of light. In an embodiment, light source  354  is a laser. Primary input light  214  is light transmitted from a light member (in an embodiment, light source  250 ) to a waveguide (in an embodiment, waveguide  212 ). Secondary output light  216  is light transmitted from dosimatrix  220  to waveguide  212 . Secondary input light  218  is light transmitted from waveguide  212  to dosimatrix  220 . Primary output light  222  is light transmitted from a waveguide (in an embodiment, waveguide  212 ) to a light member (in an embodiment, light member  248 ). Primary compensation input light  242  is light transmitted from a light member (in an embodiment, light source  258 ) to a waveguide (in an embodiment, temperature-compensating waveguide  238 ). Secondary compensation output light  244  is light transmitted from a waveguide (in an embodiment, temperature-compensating waveguide  238 ) to a compensation resonator (in an embodiment, compensation resonator  236 ). Primary compensation output light  246  is light transmitted from a waveguide (in an embodiment, temperature-compensating waveguide  238 ) to a light member (in an embodiment, light source  258 ). Resonant frequency  240  is the frequency of light transmitted from a compensation resonator  236  to compensation waveguide  238 . 
     Light detector  252  produces a measurable voltage or current that can be quantified, in response to incident light. Light detector  260  produces a measurable voltage or current that can be quantified, in response to incident light First detector  344  produces a measurable voltage or current that can be quantified, in response to incident light Second detector  346  produces a measurable voltage or current that can be quantified, in response to incident light Detector  351  produces a measurable voltage or current that can be quantified, in response to incident light. First detector  359  produces a measurable voltage or current that can be quantified, in response to incident light Second detector  364  produces a measurable voltage or current that can be quantified, in response to incident light 
     Optical filter  342  removes a portion of the frequency spectrum of the incident light. Beam splitter  343  divides incident light flux into two or more paths. Combiner  349  combines multiple light paths into one output light path. Optical amplifier  350  increases the intensity of the primary light (an embodiment is an erbium-doped fiber amplifier). Controller  353  is an electronic device that controls other elements such as light members and optical amplifiers. Splitter  355  divides incident light flux into two or more paths. 
     In an embodiment, thermometer is produced by forming the optical resonator (e.g., a ring resonator) on a silicon-on-insulator substrate (SOI). The substrate can include a stacked structure having a first silicon layer (e.g., 220 nm thick) and a buried silicon dioxide layer (BOX, e.g., 2 μm thick) interposed between the first silicon layer and a bottom silicon layer (e.g., 670 μm thick). The SOI can be a wafer or die. A positive or negative tone electron beam resist is spin coated on the SOI substrate and baked at a temperature above a glass transition temperature of the resist. The substrate is subjected to electron beam to provide the optical resonator. During development of the resist from an exposed resist (e.g., the positive tone electron beam resist) or an unexposed resist (e.g., the negative tone electron beam resist), portions of the first silicon layer are removed by a solvent post lithography to form an etch mask. The resulting structure is subjected to dry etching by, e.g., an inductively coupled plasma reactive ion etch where an unmasked portion of the first silicon layer is etched through to the BOX layer. The etch mask is dissolved in a solvent to provide the thermometer. In some embodiment, the dielectric layer (e.g., silicon dioxide) is disposed on the thermometer by plasma-enhanced chemical vapor deposition to provide, e.g., a 2 μm thick silicon dioxide dielectric layer. 
     According to an embodiment, the Bragg grating or Bragg coupler can be formed by irradiating the optical resonator or the waveguide with an ultraviolet light (e.g., from an ultraviolet laser such as ArF or KrF) to modify an index of refraction of the illuminated material. An angle between an ultraviolet light beam and optical resonator (or waveguide) can determine a period of protrusions and depressions of the Bragg grating or coupler and thus the Bragg wavelength. A plurality of ultraviolet laser beams can be used to create a periodic phase mask (photomask) in a phase mask technique, e.g., by using two first-order diffracted ultraviolet laser beams. A non-periodic phase mask can be used to obtain other patterns of the Bragg grating or coupling. In another embodiment, a point-by-point Bragg grating or coupler is created by point-by-point writing a pattern with a focused laser beam. In some embodiments, an infrared light having intense femtosecond pulses is used to produce the Bragg grating or coupler. 
     According to an embodiment Bragg grating is fabricated on a silicon-on-insulator substrate (SOI) that includes the topmost silicon layer (e.g. 220 nm thick), thick buried silicon dioxide layer (BOX) e.g. 3 μm thick, and the supporting bottom silicon layer (e.g. 670 μm thick). The SOI can be wafer or die. A positive or negative tone electron beam resist is spin coated on the SOI substrate, and the resultant structure is baked at a temperature greater than a glass transition temperature of the resist. The substrate is subjected to electron beam exposure to provide the Bragg grating. Electron beam lithography defines the structure of Bragg grating and is an etch mask. A subsequent dry etch process such an inductively coupled plasma reactive ion etch where an unmasked portion of the first silicon layer is etched through to the BOX layer. The etch mask is dissolved in a solvent to provide the thermometer. In some embodiments, the dielectric layer (e.g., silicon dioxide) is disposed on the thermometer by plasma-enhanced chemical vapor deposition to provide, e.g., a 2 μm thick silicon dioxide dielectric layer. 
     A physical size or material of the thermometer is selected based on a wavelength range of the input light, output light, or resonant frequency of the optical resonator. The optical resonator can have an outer diameter from 9 μm to 900 μm, specifically 9 μm to 700 μm, and more specifically from 9 μm to 150 μm. A distance between the optical resonator and the waveguide can be less than or equal to 300 nm, specifically 10 μm to 200 μm, and more specifically from 20 nm to 150 nm. 
     In an embodiment, the thermometer is configured to measure a temperature from 300 milliKelvin (mK) to 500 K, specifically 300 mK to 450 K, and more specifically 300 mK to 325 K. According to an embodiment, the thermometer is configured to measure a temperature, wherein an uncertainty in a measured temperature is less than or equal to 10 mK. In certain embodiments, the thermometer has a temperature resolution greater than or equal to 1 mK. The thermometer has a temperature-dependent shift in a resonance wavelength from (picometers per Kelvin (pm/K) to 150 pm/K. According to an embodiment, for resolving a temperature difference, the thermometer has a resolution greater than or equal to 1 mK (i.e., the thermometer resolves a temperature difference of at least 1 mK), specifically greater than or equal to 80 μK, and more specifically greater than or equal to 10 μK. 
     The thermometer has advantageous optical properties. In an embodiment, the input light to the thermometer includes a wavelength from 200 nm to 10 μm, specifically 400 nm to 3 μm, and more specifically 500 nm to 2 μm. The resonant frequency of the optical resonator includes a wavelength from 200 nm to 10 μm, specifically 400 nm to 3 μm, and more specifically 500 nm to 2 μm. The output light of the thermometer includes a reduced transmission of the resonant frequency with respect to the input light. A free spectral range of the optical resonator is greater than 0.001 nm and specifically from 0.1 nm to 20 nm. A bandwidth of the optical resonator is from 0.0001 nm to 1 nm. A quality factor (Q-factor) of the optical resonator is from 1 to 106 and specifically from 100 to 100,000. It is contemplated that the optical resonator can have an increased Q-factor by including a Bragg reflector. 
     In an embodiment, a group index is from 1 to 5, specifically from 1.5 to 4.7. The thermometer operates over a wide range of input light power provided the resonant wavelength can be communicated from the waveguide to the optical resonator. Moreover, the power can be as large as a damage threshold of the optical resonator or waveguide, e.g., greater than or equal 10 microwatts (μW), specifically greater than 20 μW, and more specifically 50 μW up to the damage threshold. 
     The thermometer has numerous advantages and benefits. The thermometer is useful to detect a temperature with a sub-mK resolution. The thermometer has a low noise level and low thermal mass. Moreover, the thermometer is substantially unaffected by electromagnetic interference and has applications wherever a thermometer can be used provided light can be coupled into the thermometer with transmission from the waveguide to the optical resonator. Exemplary areas of application include, but are not limited to, medicine, aerospace, analytical instrumentation, microfluidic, and the like. 
     The thermometer leverages frequency metrology to achieve mechanical and environmental stability. A silicon-based thermometer that includes the optical resonator resolves temperature differences of 1 mK using, e.g., by scanning the input wavelength over the resonant frequency of the optical resonator, and a noise floor of 80 μK or better is achieved for measuring a temperature difference, e.g., by using a side-of-fringe method where constant power input light is incident at the waveguide as discussed below. 
     Additionally, while certain conventional thermometers such as a platinum resistance thermometer is sensitive to mechanical shock, the thermometer herein has a response that is substantially independent of mechanical shock such that the thermometer is configured to operate stably in a presence of a perturbing vibration and can be disposed on a plurality of actively vibrating articles, e.g., airplanes, satellites, automobiles, buildings, shoes, and the like. Moreover, the thermometer can be inexpensively manufactured compared to many current commercially available thermometers. 
     The thermometer beneficially includes an optical resonator that has a periodic notch filter-like thermal response where the resonant wavelength shows a temperature-dependent change due to thermal expansion or thermo-optic effect. 
     Advantageously, a resonance frequency of the thermometer does not vary over a wide range of relative humidity levels, e.g., a relative humidity greater than 17 percent relative humidity (% RH), and more specifically 26% RH, based on amount of water vapor in a gas surrounding the optical resonator. As such, a change in resonance frequency is due to a temperature change, which does not depend on a change in humidity of an environment in which the thermometer is disposed. 
     The thermometer has numerous uses. In an embodiment, the thermometer has a temperature response such that the output light from the waveguide depends on a temperature of the optical resonator. For the optical resonator that includes the ring resonator, a change in the resonant frequency (corresponding to resonant wavelength λ r ) arises from a change in refractive index (n) of the optical resonator or a change of a physical dimension of the optical resonator that occurs in response to a change in temperature of the optical resonator. The resonance wavelength λ r  for a mode number (m) of a ring resonator is λ r (m)=[n eff  (λ,T r )×L(T r )]/m, where λ is a vacuum wavelength; n eff  is an effective refractive index of the ring resonator; m is a mode number; L is a ring perimeter; and T r  is a temperature of the optical resonator. A change in the resonant wavelength of the optical resonator is given by formula (1) 
               Δ   ⁢           ⁢     λ   r       =     Δ   ⁢           ⁢     T   r     ⁢       λ   r     (           ∂     n   eff         ∂     T   r         +       n   eff     ⁢       ∂   L       ∂     T   r         ⁢     1   L           n   g       )             
where group index n g  is given by
 
     
       
         
           
             
               n 
               g 
             
             = 
             
               
                 n 
                 eff 
               
               - 
               
                 
                   λ 
                   r 
                 
                 ⁢ 
                 
                   
                     ∂ 
                     
                       n 
                       eff 
                     
                   
                   
                     ∂ 
                     
                       λ 
                       r 
                     
                   
                 
               
             
           
         
       
     
     With reference to  FIG. 32 , in an embodiment, a process for acquiring a temperature from the thermometer includes providing the thermometer that includes the optical resonator and that has first transmission curve C 1  at first temperature T 1 , second transmission curve C 2  at second temperature T 2 , and third transmission curve C 3  at third temperature T 3 . The optical resonator has first resonant wavelength Xr 1  at first temperature T 1 , second resonant wavelength Xr 2  at second temperature T 2 , third resonant wavelength Xr 3  at third temperature T 3 . The input light at wavelength λ 0  is provided to the waveguide and transmission of the output light at wavelength λ 0  is detected as the thermometer is subjected to a temperature change that includes first temperature T 1 , second temperature T 2 , and third temperature T 3 . In this manner, the output light detected at wavelength λ 0  establishes an intensity curve as shown in  FIG. 33  for a graph of intensity versus temperature of the thermometer. Here, the output has first transmission intensity I 1 , second transmission intensity  12 , third transmission intensity I 3  respectively at first temperature T 1 , second temperature T 2 , and third temperature T 3 . 
     Furthermore, first resonant wavelength λr 1  at first temperature T 1 , second resonant wavelength λr 2  at second temperature T 2 , third resonant wavelength Xr 3  at third temperature T 3  can be detected using a detector, e.g., a wavemeter. Such results are shown in  FIG. 14C  for a graph of resonant wavelength versus temperature. Information in the graph shown in  FIG. 14C  and knowledge of intensity data provides determination of an unknown temperature of temperature change of the thermometer. According to an embodiment, a process for determining an unknown temperature or change in temperature includes detecting an intensity of output light at a wavelength and comparing an intensity of output light at the wavelength to an intensity curve to determine the temperature, temperature change, or combination thereof. 
     According to an embodiment, the thermometer includes the thermal member to change a temperature of the thermometer by providing a controlled and defined heat source to the thermometer, e.g., the optical resonator. The change in resonant frequency of the optical resonator is measured and a transmission response of output light is detected to determine if the thermometer is responding as expected based on either a theoretical response curve or a calibration curve for the thermometer. 
     In an embodiment, a process for determining a thermal property includes providing a thermometer that includes a substrate, an optical resonator disposed on the substrate and comprising an optical resonance and a waveguide disposed on the substrate proximate to the optical resonator. The process also includes subjecting the optical resonator to a first temperature, receiving (by the waveguide) an input light comprising a wavelength having a first transmission intensity through the waveguide at the first temperature, receiving (by the optical resonator from the waveguide) a first amount of the wavelength at the first temperature, subjecting the optical resonator to a second temperature, receiving (by the optical resonator from the waveguide) a second amount of the wavelength at the second temperature, changing the first transmission intensity to a second transmission intensity corresponding to the second amount, and analyzing the first transmission intensity and the second transmission intensity to determine the thermal property that includes the first temperature, the second temperature, a difference between the first temperature and the second temperature, or a combination comprising at least one of the foregoing. 
     According to an embodiment, the process for determining the thermal property further includes subjecting the optical resonator to a temperature change that includes the first temperature and the second temperature by applying an amount of electrical power to a thermal member disposed on the substrate to achieve the first temperature, the second temperature, or a combination comprising at least one of the foregoing; and comparing a change in the first transmission intensity and the second transmission intensity, the difference between the first temperature and the second temperature, or a combination comprising at least one of the foregoing to a reference value for the amount of electrical power. 
     In an embodiment, with reference to  FIG. 34A , thermometer system  340  includes light source  341  to provide primary compensation input light  242  to thermometer  345 . Light source  341  is a broad band source (e.g., a lamp), a laser, or a combination thereof. Optical filter  342  (e.g., a Fabry-Perot cavity) is optionally disposed in a path of the input light to select a narrow bandwidth of input light to be communicated to thermometer  345 . Beam splitter  343  is optionally used to provide a portion of the input light to first detector  344 , e.g., a wavemeter to measure the wavelength of the input light, a photodiode, a power meter, and the like. It is contemplated that a wavelength of the input is measured using, e.g., a wavemeter, an etalon, a spectrometer, a wavelength cell, a spectrum analyzer, and the like. Output light from thermometer  345  is sent to second detector  346 , which is, e.g., a light detector such as a photo-diode, charge coupled device, semiconductor detector (e.g., InGaAs), photomultiplier tube, and the like. 
     According to an embodiment, with reference to  FIG. 34B , thermometer system  340  includes thermometer  345  having an add-drop arrangement of an optical resonator and waveguides. Here, optional optical filter  342  is absent due to the self-filtering behavior of an auxiliary waveguide in combination with the optical resonator. 
     In an embodiment, with reference to  FIG. 35A , thermometer system  340  includes thermometer  345  to receive input light from first light source  347  (e.g., a read-out laser) or second light source  348  (e.g., a cooling laser) via combiner  349  (e.g., a multiplexer or lock-in amplifier). Output light from thermometer  345  is directed to optical amplifier  350  and detected by detector  351  (e.g., a spectrum analyzer). Here, the side bands of second light source  348  are detected, and a ratio of an area of a side band or intensity is determined to calculate phonon occupancy, which is used in a Boltzmann&#39;s law calculation to provide temperature of the thermometer. 
     According to an embodiment, with reference to  FIG. 35B , thermometer system  340  includes controller  353  (e.g., a microprocessor, computer, and the like) in communication with light source  354  that provides input light to splitter  355  and control thermometer  356 , including a plurality of thermometers, e.g., first thermometer  357  and second thermometer  358  to provide a thermal calibration response for control thermometer  184 . Output light from control thermometer  356  is sent to first detector  359  whose output signal is communicated to controller  353 . A plurality of test thermometers (including the thermometer herein), e.g., first test thermometer  361 , second test thermometer  362 , and third test thermometer  363  are disposed in thermal contact with article  360  (e.g., airplane, automobile, surgical patient, desk clock, aquarium, and the like), and input light from beam splitter  355  is directed in series (or parallel) to first test thermometer  361 , second test thermometer  362 , and third test thermometer  363 , which provide output light to second detector  364 . An output signal is directed to the controller  353 . Output signals from test thermometers ( 202 ,  204 ,  206 ) can be compared to reference signals from control thermometer  356 . 
     In some embodiments, the thermometer is a self-diagnosing thermometer that includes a thermal member such that the thermometer is remotely interrogated after installation in an article. Here, the thermal member provides a known heat load to the optical resonator and output light is collected to determine if a change in the resonant frequency has occurred with respect to an expected value of change in the resonant frequency for the known heat load. 
     According to an embodiment, a process for self-diagnosing a thermometer includes disposing a thermal member proximate to an optical resonator of the thermometer, providing an input light to the waveguide, detecting output light from the waveguide, and measuring transmission intensity. The thermometer is at a first temperature, and a wavelength of the input light is changed such that the wavelength is swept over the resonance frequency of the optical resonator. The resonance frequency is determined. The process also includes providing an amount of electrical power to the thermal member, changing the temperature of the optical resonator, and changing the wavelength of the input light, wherein a wavelength range includes the resonance frequency. The resonance frequency is determined by detecting from the output light. In an embodiment, a plurality of heating events delivers a plurality of different amounts of electrical power to the thermal member. For a single measurement, a change in resonance frequency provides a change in the resonant frequency corresponding to a first temperature and a second temperature. For the plurality of heating events, the process also includes determining whether a change in the resonance frequency is linear with respect to a change in temperature. In an embodiment, an alert signal is communicated, e.g., to a user, in response to the change in resonant frequency being nonlinear with respect to temperature change. Such nonlinear behavior may be associated with operation of the thermometer in a non-calibrated fashion. Thus, the self-diagnosing behavior of the thermometer provides a way to perform a self-check service by a user or an automatic drive (e.g., an electronic controller such as programmed computer) to determine if the thermometer is performing within an acceptable parameter. 
     According to an embodiment, the thermometer is subjected to temperature-wavelength calibration to determine the response (e.g., a wavelength shift) determined at a plurality of temperatures that includes an operation temperature. A mathematical function (e.g., a polynomial) is fit to calibration data to create a conversion for a measured resonant wavelength (or wavelength shift) to a temperature. 
     In an embodiment, a process for self-calibrating a thermometer includes providing a thermometer (including a waveguide and optical resonator disposed on a substrate), determining the resonant frequency of the optical resonator, and providing a stable input light tuned to a longer wavelength side of the resonant frequency to cool the resonator (e.g., a detuned laser). A spectrum analyzer can be used to determine the frequency and intensity of the output light. Under a laser cooling condition, the spectrum analyzer displays a signal corresponding to the wavelength of the detuned laser (e.g., a frequency and intensity) and a plurality (e.g., two) side bands that occur, e.g., equidistantly from the detuned laser frequency. The self-calibration process further includes determining an area of each side band and determining phonon occupancy number P. Phonon occupancy number P is determined from the data by using a phonon occupancy equation such as P=1/[(A(LF)/A(HF))−1], where P is the phonon occupancy number; A(LF) is an area of a low frequency side band, and A(HF) is an area of a high frequency side band. The temperature of the optical resonator is determined from phonon occupancy number P by applying Boltzmann&#39;s law. In a particular embodiment, a thermodynamic temperature is determined from phonon occupancy number P to eliminate a temperature artifact such as a triple point water such as that used in temperature standards, e.g., the International Temperature Scale of 1990 (ITS-90), to approximate a thermodynamic temperature. 
     Photonic dosimeter  200  can be made in various ways. In an embodiment, a process for making photonic dosimeter  200  includes forming dosimatrix  220  on a silicon-on-insulator substrate (SOI). The substrate can include a stacked structure having a first silicon layer (e.g., 220 nm thick) and a buried silicon dioxide layer (BOX, e.g., 2 μm thick) interposed between the first silicon layer and a bottom silicon layer (e.g., 670 μm thick). The SOI can be a wafer or die. A positive or negative tone electron beam resist is spin coated on the SOI substrate and baked at a temperature above a glass transition temperature of the resist. The substrate is subjected to electron beam to provide the optical resonator. During development of the resist from an exposed resist (e.g., the positive tone electron beam resist) or an unexposed resist (e.g., the negative tone electron beam resist), portions of the first silicon layer are removed by a solvent post lithography to form an etch mask. The resulting structure is subjected to dry etching by, e.g., an inductively coupled plasma reactive ion etch where an unmasked portion of the first silicon layer is etched through to the BOX layer. The etch mask is dissolved in a solvent to provide the dosimeter. In some embodiment, the dielectric layer (e.g., a polymer coating, such as a polyimide or polyvinyl alcohol) is disposed on the dosimeter by spin coating or drop casting to provide, e.g., a 2 μm thick layer of the dielectric polymeric layer. 
     In an embodiment, a process for making photonic calorimeter  300  includes: embedding temperature compensator  234  in radiation absorber  268  (such as graphite, polymethylmethacrylate, water) thermal isolator  262  (material, removal of material), thermal compensator  234  include compensation resonator  236  and a compensation waveguide  238 , embedded in radiation absorber  268  while ensuring thermal isolation achieved by inserting a gap between the radiation absorber  268  and the substrate or other absorbers for a multiplexed embodiment  402 . 
     The thermometer provides an optical response as a function of temperature, e.g., as shown in  FIG. 32  and  FIG. 33 . It is contemplated that photonic dosimeter  200  provides a response to cumulative dose of ionizing radiation  254  via conversion from prime state  230  to dosed state  232  as shown in panel A of  FIG. 36 . Here, at first cumulative dose C 1  of dosimatrix  220 , active element  224  is in first state S 1  corresponding to prime state  230 , wherein dosimatrix  220  has an optical resonance at first wavelength L 1 . As photonic dosimeter  200  is subjected to increasing cumulative dose of ionizing radiation  254 , dosimatrix  220  obtains cumulative dose C 2 , and active element  224  converts from prime state  230  to dosed state  232 , wherein dosimatrix  220  has an optical resonance at second wavelength L 2 . As a result, without changing a wavelength of primary input light  214  received by waveguide  212 , primary output light  222  from waveguide  212  changed due to a change in secondary output light  216  because of the shift in wavelength of the optical resonance of dosimatrix  220  caused by increasing cumulative dose of ionizing radiation  254  received by dosimatrix  220  that converted from prime state  230  to dosed state  232 . Panel B of  FIG. 36  shows a continuous conversion of state of active element  224  from S 1  at cumulative dose C 1  with wavelength L 1  of optical resonance of dosimatrix  220 , to S 2  at cumulative dose C 2  with wavelength L 2  of optical resonance of dosimatrix  220 , to S 3  at cumulative dose C 3  with wavelength L 3  of optical resonance of dosimatrix  220 , to S 4  at cumulative dose C 4  with wavelength L 4  of optical resonance of dosimatrix  220 , and to S 5  at cumulative dose C 5  with wavelength L 5  of optical resonance of dosimatrix  220 . With regard to prime state  230  and dosed state  232  of dosimatrix  220 , any state at a selected cumulative dose (e.g., C 2 ) can be selected as a primary state, and any state at a cumulative dose (e.g., C 8 , which is not shown in panel B of  FIG. 36  but would be greater than C 5 ) greater than the selected cumulative dose can be a dosed state. Accordingly, photonic dosimeter  200  can be used multiple times, can be used over differing amounts of cumulative dose, can be used over an arbitrary period of dosing, or can be subjected to continuous or intermittent dosing with ionizing radiation  254 . 
     Photonic dosimeter  200  has numerous advantageous and unexpected benefits and uses, including performing dosimetry In an embodiment, a process for performing dosimetry with photonic dosimeter  200  includes: receiving, by waveguide  212 , primary input light  214 ; producing, by waveguide  212 , secondary input light  218  from primary input light  214 ; receiving, by dosimatrix  220 , secondary input light  218  from waveguide  212 ; producing, by dosimatrix  220 , secondary output light  216  from secondary input light  218 ; receiving, by waveguide  212 , secondary output light  216  from dosimatrix  220 ; producing, by waveguide  212 , primary output light  222  from secondary output light  216 ; subjecting dosimatrix  220  to ionizing radiation  254 ; and changing active element  224  from prime state  230  to dosed state  232  in response to receiving ionizing radiation  254  by dosimatrix  220  to perform dosimetry. The process for performing dosimetry further can include determining a first dosimeter response based on secondary output light  216  prior to subjecting dosimatrix  220  to ionizing radiation  254 . Additionally, the process for performing dosimetry can include determining a second dosimeter response based on secondary output light  216  after subjecting dosimatrix  220  to ionizing radiation  254 . In some embodiment, the process for performing dosimetry includes determining a dose of ionizing radiation  254  absorbed by dosimatrix  220  from first dosimeter response and second dosimeter response. It is contemplated that determining the dose includes performing an inverse radiation-transport simulation; and determining an energy absorbed per unit mass of dosimatrix  220  from changing active element  224  from prime state  230  to dosed state  232 . Moreover, the first dosimeter response and the second dosimeter response can differ in a resonance frequency, an amount of transmission, or a combination of the foregoing differences. The process for performing dosimetry also can include logging a temperature history of photonic dosimeter  200  by: receiving, by compensation waveguide  238 , primary compensation input light  242 ; producing, by compensation waveguide  238 , resonant frequency  240  from primary compensation input light  242 ; receiving, by compensation resonator  236 , resonant frequency  240  from compensation waveguide  238 ; producing, by compensation resonator  236 , secondary compensation output light  244  from resonant frequency  240 ; receiving, by compensation waveguide  238 , secondary compensation output light  244  from compensation resonator  236 ; producing, by compensation waveguide  238 , primary compensation output light  246  from secondary compensation output light  244 ; and monitoring primary compensation output light  246  as a function of time to log the temperature history of photonic dosimeter  200 . Here, primary compensation output light  246  changes as a function of temperature of compensation resonator  236 . According to an embodiment, in the process for performing dosimetry, changing prime state  230  to dosed state  232  includes changing a physical property or a chemical property of active element  224  by ionizing radiation  254 . 
     In the process for performing dosimetry, primary light  214  is transmitted from a light member  248  and can originate from a light source  250  and receiving, by waveguide  212 , primary input light  214  can include is transmitted into dosimeter  200 . In a particular embodiment, primary light from a laser is swept over a wavelength range and transmitted to the waveguide on a dosimeter via fiber optic. 
     In the process for performing dosimetry, producing, by waveguide  212 , secondary input light  218  from primary input light  214  can be transmitted to the dosimatrix  220 . In a particular embodiment, light in the waveguide is coupled to the optical resonator. 
     In the process for performing dosimetry, receiving, by dosimatrix  220 , secondary input light  218  from waveguide  212  can interact with the dosimatrix  220  and the active element  224 . In a particular embodiment, frequencies of light resonant with the optical resonator are trapped in the resonator; transmitted light will show intensity changes around the resonant frequencies. 
     In the process for performing dosimetry, producing, by dosimatrix  220 , secondary output light  216  from secondary input light  218  can be transmitted to the waveguide  212 . In a particular embodiment, light in the optical resonator is coupled into the waveguide. 
     In the process for performing dosimetry, producing, by waveguide  212 , primary output light  222  from secondary output light  216  can be transmitted to a light member  248 , and subsequently transmitted to a light detector  252 . In an embodiment, light is transmitted from the waveguide to the detector by fiber optic cable. 
     In the process for performing dosimetry, subjecting dosimatrix  220  to ionizing radiation  254  can change the state of dosimatrix  220  from the prime state to the dosed state. In an embodiment, the dosimatrix is placed under a source of ionizing radiation and exposed to ionizing radiation. 
     In the process for performing dosimetry, changing active element  224  from prime state  230  to dosed state  232  in response to receiving ionizing radiation  254  by dosimatrix  220  can include changes in resonance frequency, intensity and linewidth that are transmitted to the secondary light. 
     In the process for performing dosimetry, determining a first dosimeter response based on secondary output light  216  prior to subjecting dosimatrix  220  to ionizing radiation  254  can include measuring and recording spectral characteristics of output light  216 . In an embodiment, the frequency characteristics of the output light are measured. 
     In the process for performing dosimetry, determining a second dosimeter response based on secondary output light  216  after subjecting dosimatrix  220  to ionizing radiation  254  can include measuring and recording spectral characteristics of output light  216 . In an embodiment, the frequency characteristics of the output light are measured. 
     In the process for performing dosimetry, determining a dose of ionizing radiation  254  absorbed by dosimatrix  220  from first dosimeter response and second dosimeter response can include determining differences in the responses. In an embodiment, the frequency responses before and after exposure to ionizing radiation are compared; changes to frequency characteristics are functionally correlated to absorbed dose. 
     In the process for performing dosimetry, performing an inverse radiation-transport simulation (e.g., using Monte Carlo methods) can include modeling of electromagnetic interactions of radiation (e.g. photons, charged particles and neutrons) with the dosimeter for multiple input parameters of ionizing radiation using a radiation transport Monte Carlo software (e.g., Geant4) by inputting the dosimeter physical characteristics into the model and running the model for multiple (e.g., millions) of ionizing radiation particles or photons, producing model results for the absorbed energy in the dosimatrix and temperature increase in the active element. 
     In the process for performing dosimetry, determining an energy absorbed per unit mass of dosimatrix  220  from changing active element  224  from prime state  230  to dosed state  232  can include combining the results of the inverse radiation-transport with the change in response of dosimeter from prime state to dosed state to convert dosimeter response to the energy absorbed per unit mass can include combining the absorbed energy predicted by the Monte Carlo model with the absorber mass input into the model to determine absorbed energy per unit mass corresponding to various responses of the temperature compensator. 
     In the process for performing dosimetry, logging a temperature history of photonic dosimeter  200  by receiving, by compensation waveguide  238 , primary compensation input light  242  and can include monitoring the frequency response of a compensation resonator that can be located near the dosimatrix. 
     In the process for performing dosimetry, producing, by compensation waveguide  238 , secondary compensation output light  244  which can be transmitted to the compensation resonator  236 . In a particular embodiment, light in the waveguide is evanescently coupled to the optical resonator. 
     In the process for performing dosimetry, receiving, by compensation resonator  236 , resonant frequency  240  can be transmitted to the compensation waveguide  238 . In a particular embodiment, light in the optical resonator is evanescently coupled to the waveguide. 
     In the process for performing dosimetry, producing by compensation waveguide  238 , primary compensation output light  246  is communicated to light detector  258 . In an embodiment, output light is communicated to a detector using a fiber optic cable. 
     In the process for performing dosimetry, monitoring primary compensation output light  246  as a function of time to log the temperature history of photonic dosimeter  200  can include measuring peak frequency, linewidth, intensity. In an embodiment, this involves locking a laser to the optical resonator, and its frequency can be monitored using a wavemeter. 
     In the process for performing dosimetry, in changing prime state  230  to dosed state  232 , changing a physical property or a chemical property of active element  224  by ionizing radiation  254  can include changes in temperature, strain, density, oxidation and refractive index. In an embodiment, dosing will result in frequency changes in the resonator, and these changes are combined with the response of a dosimatrix to improve the calculation by accounting for temperature-induced frequency changes. 
     In an embodiment, photonic calorimeter  300  provides a response to receipt of ionizing radiation  254 , wherein radiation absorber  268  produces heat from absorption of ionizing radiation  254  as shown in  FIG. 36 . Here, photonic calorimeter output signal (e.g., primary compensation output light  246 ) changes as a function of an amount of ionizing radiation  254  received by radiation absorber  268 . Accordingly, photonic calorimeter  300  can be used multiple times, can be used over differing amounts of ionizing radiation  254 , can be used over an arbitrary period, or can be subjected to continuous or intermittent presence of ionizing radiation  254 . With reference to  FIG. 38 , panel A shows an optical transmission of compensation resonator  236  versus frequency of resonant frequency  240  at a first temperature of radiation absorber  268 . Here, compensation resonator  236  has optical transmission I 0  at frequency F 0  that increases to optical transmission  14  at frequency F 2 . At the first temperature, compensation resonator  236  has an optical resonance at first resonant frequency FR1 with intensity I 1 . Compensation resonator  286  has optical transmission I 0  at final frequency FN. When subjected to ionizing radiation  254 , radiation absorber  268  absorbs ionizing radiation  254  and converts ionizing radiation  254  to heat. Accordingly, the temperature of radiation absorber  268  increases from the first temperature to a second temperature, wherein the second temperature is greater than the first temperature. With reference to panel B of  FIG. 38 , at the second temperature, the optical resonance of compensation resonator  286  decreases to second resonance frequency FR2. In this manner, photonic calorimeter  300  optically associates a shift in optical resonance of compensation resonator  236  with heat produced by radiation absorber  268  in response to absorption of ionizing radiation  254  by radiation absorber  268 . Moreover, since the optical resonance of compensation resonator  236  changes as a function of temperature, secondary compensation output light  244  and primary compensation output light  246  likewise change as a function of temperature so that detector  258  outputs a signal indicative of an amount of ionizing radiation  254  received by radiation absorber  268 , an amount of heat produced by radiation absorber  260 , or a temperature of radiation absorber  268 . 
     Photonic calorimeter  300  has numerous advantageous and unexpected benefits and uses, including performing calorimetry. In an embodiment, a process for performing calorimetry with photonic calorimeter  300  includes: receiving, by compensation waveguide  238 , primary compensation input light  242 ; producing, by compensation waveguide  238 , secondary compensation light  244  from primary compensation input light  242 ; receiving, by compensation resonator  236 , secondary compensation light  244  from compensation waveguide  238 ; producing, by compensation resonator  236 , resonant frequency  240  output light; receiving, by compensation waveguide  238 , resonant frequency  240  output light from compensation resonator  236 ; producing, by compensation waveguide  238 , primary compensation output light  246  from secondary compensation output light  244 ; subjecting radiation absorber  268  to ionizing radiation  254 ; producing, by radiation absorber  268 , heat from ionizing radiation  254 ; communicating the heat to compensation resonator  236 ; and changing the optical resonance of compensation resonator  236  in response to producing heat from ionizing radiation  254  by radiation absorber  268  to perform calorimetry. The process for performing calorimetry further can include determining a first calorimeter response based on primary compensation output light  246  prior to subjecting radiation absorber  268  to ionizing radiation  254 . The process for performing calorimetry further can include determining a second calorimeter response based on primary compensation output light  246  after subjecting radiation absorber  268  to ionizing radiation  254 . The process for performing calorimetry further can include determining an amount of ionizing radiation  254  absorbed by radiation absorber  268  from the first calorimeter response and the second calorimeter response. It is contemplated that determining the amount of ionizing radiation  254  absorbed by radiation absorber  268  can include performing an inverse Monte Carlo conversion from a temperature change of radiation absorber  268  due to absorption of ionizing radiation  254 ; and determining an energy absorbed per unit mass of radiation absorber  268  from heating with the inverse Monte Carlo conversion. In the process for performing calorimetry, the first calorimeter response and the second calorimeter response can differ in a resonance frequency, an amount of transmission, or a combination including at least one of the foregoing differences. 
     In the process for performing calorimetry, receiving, by compensation waveguide  238 , primary compensation input light  242  can include physical or evanescent coupling of input light  242  with compensation waveguide  238 . 
     In the process for performing calorimetry, producing, by compensation waveguide  238 , secondary compensation light  244  from primary compensation input light  242  can include transmission of light through waveguide  238 . 
     In the process for performing calorimetry, receiving, by compensation resonator  236 , secondary compensation light  244  from compensation waveguide  238  can include physical or evanescent coupling of secondary compensation light  244  to compensation resonator  236 . 
     In the process for performing calorimetry, producing, by compensation resonator  236 , resonant frequency  240  output light can include transmission of light through compensation resonator  236 . 
     In the process for performing calorimetry, receiving, by compensation waveguide  238 , resonant frequency  240  output light from compensation resonator  236  can include physical or evanescent coupling of light to compensation waveguide  238 . 
     In the process for performing calorimetry, producing, by compensation waveguide  238 , primary compensation output light  246  from secondary compensation output light  244  can include transmission of light through waveguide  238 . 
     In the process for performing calorimetry, subjecting radiation absorber  268  to ionizing radiation  254  can produce secondary radiation, which can include photons and electrons, that transfer energy to the radiation absorber  268  in the form of heat can include placing radiation absorber  268  in the path of a radiation beam. 
     In the process for performing calorimetry, producing, by radiation absorber  268 , heat from ionizing radiation  254  can be communicated from the radiation absorber  268  to the compensation resonator  236  by processes including thermal thermalization of electrons and thermal conduction to compensation resonator  236 . 
     In the process for performing calorimetry, communicating the heat to compensation resonator  236  can change its optical resonance by processes including thermal variation of index of refraction of the compensator resonator  236 . 
     In the process for performing calorimetry, changing the optical resonance of compensation resonator  236  in response to producing heat from ionizing radiation  254  by radiation absorber  268  can indicate a temperature change in the temperature compensator  234  by processes including the thermal variation of index of refraction of the temperature compensator  234 . 
     In the process for performing calorimetry, determining a first calorimeter response based on primary compensation output light  246  prior to subjecting radiation absorber  268  to ionizing radiation  254  can indicate temperature of the temperature compensator  234  for the prime state by methods including determining the calorimeter response without ionizing radiation  254  incident. 
     In the process for performing calorimetry, determining a second calorimeter response based on primary compensation output light  246  after subjecting radiation absorber  268  to ionizing radiation  254  can indicate temperature of the temperature compensator  234  for the dosed state by methods including determining the calorimeter response after ionizing radiation  254  has been incident on radiation absorber  268  for a finite amount of time. 
     In the process for performing calorimetry, determining an amount of ionizing radiation  254  absorbed by radiation absorber  268  from the first calorimeter response and the second calorimeter response can include determining differences in the responses by subtracting the second calorimeter response from the first calorimeter response. 
     In the process for performing calorimetry, in determining the amount of ionizing radiation  254  absorbed by radiation absorber  268 , performing an inverse Monte Carlo conversion from a temperature change of radiation absorber  268  due to absorption of ionizing radiation  254  can include modeling of electromagnetic interactions of radiation (e.g. photons, charged particles and neutrons) with the calorimeter  300  for multiple likely input parameters of ionizing radiation  254  using a radiation transport Monte Carlo software by inputting the photonic calorimeter  300  physical characteristics into the model and running the model for multiple (e.g. millions) of ionizing radiation  254  particles or photons, producing model results for the absorbed energy in the radiation absorber  268  and temperature increase in the compensation resonator  236 . 
     In the process for performing calorimetry, determining an energy absorbed per unit mass of radiation absorber  268  from heating with the inverse Monte Carlo conversion can combining the results of the inverse radiation-transport with the change in response of temperature compensator from prime state to dosed state to convert temperature compensator response to the energy absorbed per unit mass can include combining the absorbed energy predicted by the Monte Carlo model with the absorber mass input into the model to determine absorbed energy per unit mass corresponding to various responses of the temperature compensator. 
     In the process for performing calorimetry, with regard to the first calorimeter response and the second calorimeter response, differing in a resonance frequency can include change in resonance frequency due to heating of the temperature compensator  234 . It is contemplated that differing in an amount of transmission can include differing in the transmission of the temperature compensator  234 . 
     The process for performing calorimetry further can include calibration of the temperature compensator  234  by comparing its response to temperature to the response of a calibrated temperature compensator or thermometer. 
     Photonic dosimeter  200 , photonic calorimeter  300  and processes disclosed herein have numerous beneficial uses, including imaging of dose for industrial and medical applications. Advantageously, photonic dosimeter  200  or photonic calorimeter  300  can measure absorbed dose over a wide range of spatial scales down to 100 nm, radiation types (photons, particles), intensities and energy scales. Further, individual or groups of devices can be embedded in photonic and electronic devices, construction materials, soft materials (such as polymerics), composite materials, additively manufactured materials. 
     Moreover, photonic dosimeter  200  and processes herein have numerous advantageous properties. In an aspect, photonic dosimeter  200  provides real-time data acquisition with ca. microsecond time resolution. 
     Photonic dosimeter  200  unexpectedly overcomes problems with conventional technologies and testing, wherein the size of the conventional dosimeter is too large to resolve dose from low-energy radiation sources. Photonic dosimeter  200  overcomes this limitation by providing sub-millimeter-resolution dosimetry, with the option of embedding networks of photonic dosimeters. 
     Moreover, photonic calorimeter  300 , and processes herein have numerous advantageous properties. In an aspect, photonic calorimeter  300  provides real-time data acquisition with ca. microsecond time resolution. 
     Photonic calorimeter  300  unexpectedly overcomes problems with conventional technologies and testing, wherein the size of the conventional dosimeter is too large to resolve dose from low-energy radiation sources. Photonic calorimeter  300  overcomes this limitation by providing sub-millimeter-resolution dosimetry, with the option of embedding networks of photonic calorimeters. 
     The articles and processes herein are illustrated further by the following Examples, which are non-limiting. 
     EXAMPLES 
     Example 1 
     Radiation Hardness of Fiber Bragg Grating Thermometers 
     Photonic sensing is tolerant to harsh environments where conventional sensing technologies fail. With regard to tolerance to radiation, the impact of gamma-ray exposure on the temperature response of fiber Bragg gratings is described. At 25° C., exposures leading to an accumulated dose of up to 600 kGy result in complex dose-dependent drift in Bragg wavelength, increasing uncertainty in temperature measurements obtained if appreciable dose is delivered over the measurement interval. Temperature sensitivity is not severely impacted by integrated dose, wherein devices measure relative changes in temperature. 
     Photonic sensing involves exploiting sensitivity of the device to changes in the refractive index of the host material. For example, in a fiber Bragg grating (FBG), the resonant condition is directly proportional to the refractive index of the waveguide. A small change in the refractive index e.g., due to a rise in temperature, leads to a significant change in resonance wavelength which has been exploited for photonic thermometry. Radiation induced damage causes local point defects, dislocations, and formation of color centers that contribute to local changes in refractive index that might degrade measurement sensitivity and accuracy of a sensor. 
     In radiation environments, with dose rates ranging from a few Gy/h to a few kGy/h, devices function over years of exposure to radiation and aggregate dose accumulations exceeding 1 MGy. Optical fibers show increased attenuation with accumulated dose, and drifts in Bragg resonances occur, wherein resonance wavelength redshifts with increasing dose rate for accumulated doses below about 25 kGy. A blue shift of magnitude (&lt;0.1 nm) might occur at aggregate doses approaching 0.5 MGy. Many industrial irradiation processes deliver doses ranging from 10 Gy to 1 MGy, and dose-related shifts in Bragg wavelength contribute ≈10 K systematic uncertainty to in situ temperature measurements. Devices herein correlate the shift with dose and dose rate over irradiation conditions. 
     FBG thermometers were exposed to gamma (γ)-rays, and the thermometers were systematically exposed for FBG thermometers that included Ge-doped silica fibers with two cladding materials—polyimide and ORMOCER (Organic Modified Ceramics)-to varying levels of radiation, leading up to 600 kGy of absorbed dose. A dose-dependent change occurred in the Bragg resonance, wherein a magnitude and direction of wavelength shift vary over the dose range. The experimental measurement apparatus includes the FBG sensors that were probed with a C-band laser that was swept over the sensor resonance. Ten percent of the laser power was immediately picked up from the laser output for wavelength monitoring (absolute accuracy=0.16 pm) while the rest, after passing through an optical circulator, was injected in the FBG. Six FBG devices (three with polyimide cladding, labelled FBG  1 - 3 , and three with ORMOCER cladding, labelled FBG  4 - 6 ) were exposed to multiple dose fractions of γ-radiation to achieve dose levels ranging from 0.1 Gy to 600 kGy (1 Gy=100 rad) in the NIST high dose irradiation facility. The absorbed dose to SiO 2  in the FBG core was calculated from dose-to-water standards by Monte Carlo simulation of the FBG irradiation geometry. 
     The impact of dose on resonance peak position is shown in  FIG. 39  for FBGs  1  through  6 , in which wavelength shift vs. absorbed dose is determined relative to the peak position obtained at an absorbed dose of 0.1 kGy. Our results indicate a distinct difference in response of the two groups of FBGs within the initial 0.1 kGy of absorbed dose, with the ORMOCER-coated devices (FBGs  4 - 6 ) showing a dramatic redshift of ≈0.75(15) nm, whereas the polyimide-coated fibers (FGBs 1 through 3) exhibit small shifts that are comparable in magnitude to experimental uncertainties (1 standard deviation) as determined by reproducibility of measurements (for which representative error bars are provided on a few of the data points). For absorbed doses above 0.1 kGy, clear differences in response of the two groups of fibers are no longer discernible—all six fibers exhibited a weak tendency to blueshift with absorbed doses between 0.1 kGy and 1 kGy, while all but one showed a tendency to redshift as the accumulated dose grows to 300 kGy. The total shift in peak center for the two fibers that received 300 kGy dose, 135 pm and 165 pm, is the equivalent of ≈13.5° C. and ≈16.5° C. spurious increase in temperature, respectively (i.e. as would be registered by each device in normal thermometric monitoring). However, when FBG  3  was exposed to another 300 kGy dose, for a total integrated dose of 600 kGy, the peak center blue-shifted by 119 pm. The origins of this non-linear dose dependence of the peak center are not presently understood. 
     We also investigated the effect of radiation dose on temperature sensitivity of three other FBGs by measuring temperature dependence of the resonance wavelength before and after delivering a single dose fraction of 250 kGy. As shown in  FIG. 43 , temperature scans acquired after radiation exposure exhibit a net redshift of ≈120 pm, comparable to what is shown for FBGs  1 ,  3  and  6  in  FIG. 1  (i.e., all FBGs in the initial batch of six which had received as much dose), but the temperature sensitivity (slope of plots in  FIG. 2 ) of the FBG is not as significantly impacted by radiation dose. Hence, in view of accumulated dose, such devices provide for relative temperature measurements such as tracking temperature rise while a reactor is operating. 
     Example 2 
     Assessing Radiation Hardness of Silicon Photonic Sensors 
     Silicon photonic platforms provide optical communication. It is contemplated that such devices can be deployed in photonics-based communication and science instruments in harsh environments such as outer space, where radiation damage can occur. The impact of cobalt-60 γ-ray radiation up to 1 megagray (MGy) absorbed dose on silicon photonic devices is described, wherein systematic impact of radiation on passivated devices is absent such that passivated silicon devices were durable under harsh conditions. 
     Silicon photonic sensors are sensitive to external stimuli that produce changes in refractive index of a host material. In photonic devices, small changes in temperature can produce measurable changes in resonance peak wavelength for photonic thermometry and similar applications. This sensitivity to refractive index is geometrically increased in resonant devices such as a ring resonator or photonic crystal cavity, where refractive index sensitivity grows with quality factor. Radiation induced damage produces dislocations and other defects in crystalline structure that affect refractive index. 
     In silicon-on-insulator (SOI) based electronic devices, trapped charges and local changes in bond structure are a cause of device failure. Here, changes in the refractive index due to changes in free carrier population and damage to the Si lattice can significantly degrade the measurement sensitivity and accuracy of a photonic sensor. Unpassivated Si ring resonator devices exposed to relatively low levels of ionizing radiation (&lt;9 kGy) show a blue shift in resonance wavelength that was not observed for passivated devices exposed to ≈1.5 kGy of ionizing radiation. A photonic sensor operating in a high radioactivity environment such as a nuclear power plant is expected to receive about 1 MGy of dose per year. Under such conditions, sensor performance can be negatively impacted by changes in refractive index, covalent bond breaking, radiation induced densification, or changes in surface chemistry that can result in increased propagation losses, resulting in lower quality factors and drift in resonance wavelength of resonant devices. 
     Impact of γ-radiation up to a cumulative dose of 1 MGy (1 Gy=100 Rad) from  60 Co γ-ray radiation on silicon ring resonators and Bragg waveguides across multiple devices and chips was studied. Dose absorbed by such chips was modelled using a radiation transport Monte Carlo simulation based on engineering drawings of the source and previous measurements of the radiation field. Silicon photonic devices withstood high cumulative doses without degradation in performance. 
     Bragg waveguides and ring resonators were exposed to levels of γ-ray radiation and did not show changes in spectral characteristics. A typical Bragg waveguide transmission spectrum, shown in  FIG. 44 , does not show any systematic changes in either the peak center or the bandwidth of the Bragg waveguide rejection window. Here, the Si ring resonator and Bragg waveguide (insert) showed no significant changes in spectral characteristics as absorbed dose is increased from 0 Gy to 1048 kGy. The variation in peak center observed between the different dose spectra is found to be 8 pm and was not correlated with dose (R 2 =0.28). Similarly, variation in linewidth (2.6 pm) was poorly correlated with dose (R 2 =0.54) and was within the measurement uncertainty of ±7 pm. The linewidth in a Bragg device was directly proportional to the refractive index contrast between the waveguide and etched step regions (where the evanescent field interacts with the surrounding oxide material, sampling an effectively lower refractive index than the unetched waveguide region). A lack of change in Bragg linewidth indicated the oxide layer immediately next to the Si does not suffer any significant changes such as bond breaking or densification of the oxide layer due to radiation exposure. Similarly, a lack of significant change in peak isolation indicated the devices did not have damage to the Si surface or lattice. 
     In ring resonators, where spectral consequences of small changes in device characteristics, such as refractive index, can increase due to recirculation of light in the ring structure, significant dependence on absorbed dose was not observed. We examined impact of radiation in several ring resonator devices with quality factors (Q-factors) ranging from 5,000 to 30,000 at room temperature. As shown in  FIG. 45  and  FIG. 46 , ring resonator devices did not show dose-dependent change in the free spectral range (FSR), Q-factor, and peak position. The FSR was uncorrelated with dose (R 2 =0.08), with a standard deviation for the 4 doses of 2.5 pm (0.031%).  FIG. 45  shows Q-value (top) and peak position (bottom) of a ring resonance across three different irradiated chips (plus control chip #4) was not significantly impacted by radiation dose, wherein a number next to the symbols refer to dose (kGy) delivered on that particular date. The Q-factor decreased over time, but the decrease was the same for the control chip as for the irradiated chips and thus cannot be unambiguously ascribed to dose (see top of  FIG. 45 ). The observed decrease of 12% in Q-factor was correlated with peak input power and was reproduced when input power was doubled and indicated the observed effect was due to the device undergoing self-heating during the laser scan, not radiation damage. The small variation in absolute peak position observed for Chips  1 - 3  between irradiations (average standard deviation of [13±13] pm) was statistically indistinguishable to changes observed in the control chip. This small variability was found to be random, with the most stringent test coming from the peak position at 20° C. (measured at 0 Gy dose), which was found to be uncorrelated to dose, with R 2 =0.01. The four chips were made in the same batch and contained the same devices. The control chip traveled with other chips to and from the photonics lab to the radiation facility but was never exposed to radiation itself. 
     FSR of the devices did not show any significant changes and indicated that neither the group index nor the dispersion (parameters important in communication systems) was affected by radiation exposure. Examination of the temperature-dependent response of ring resonator devices showed temperature sensitivity was not impacted by radiation dose.  FIG. 46  shows temperature response of silicon ring resonator, wherein a top plot shows residuals from a common fit to all the data, and propagated uncertainty due to temperature measurement is shown for one point. For the data shown in  FIG. 46 , the average and standard deviation of the three responses was (76.9±0.2) pm/° C. A linear regression of response as a function of dose returned a slope of 
                   (       -   4     ±   2     )     ·     10     -   4         ⁢     pm     °   ⁢           ⁢       C   .     ⁢           ·   Gy           ,         
which was not significant at the 95% level (t=−1.8, p=0.32). The slight offset variability observed between doses (residuals shown in  FIG. 46  insert) was within the limited precision of the thin film resistance thermometer (±0.1° C.) when employed using nominal coefficients.
 
     Regarding, impact of ionizing radiation on silicon photonics devices, devices were irradiated within a self-contained, commercially produced  60 Co irradiator, and delivered doses were estimated using Monte Carlo analysis. Measurement of device characteristics such as peak center, peak width, FSR and temperature sensitivity did not show dose-dependent changes and indicated that the characteristic group index, dispersion and thermo-optic coefficient remained constant for aggregate doses up to 1 MGy (the maximum absorbed dose delivered in this study). These results contrasted with those of FBG-based sensors, where radiation induced changes in Bragg resonance result in significant drift in device characteristics. Accordingly, silicon photonics can be used to develop communication and sensor platforms for operating in harsh environments, such as industrial sterilization of health care products or radiation processing systems where doses can be in the range 15 kGy to 300 kGy, or nuclear power plants where dose rates of 10 kGy/h occur. Precision photonic sensors can be used in instrumentation used in radiotherapy clinics or space-based systems, where much lower aggregate doses (&lt;100 Gy) are more commonplace but high reliability and accuracy are involved. 
     A C-band laser was swept over the sensor resonance. Ten percent of laser power was immediately picked up from the laser output for wavelength monitoring while the rest was evanescently coupled to the photonic device under test using an optical fiber held within a few microns of the chip surface. The photonic chip was mounted on a Peltier assembly atop a 3-axis stage. Input from a platinum resistance thermometer (measurement accuracy ±0.1° C.) was communicated to a proportional-integral-derivative controller that controlled a thermoelectric cooler and maintained the temperature to within 0.02° C. of the set value. Photonic chips were fabricated using complementary metal-oxide-semiconductor (CMOS) technology. Three of the representative chips from the batch were systematically exposed to varying levels of γ-ray radiation at the NIST high-dose dosimetry laboratory, while a fourth chip, used as a control, was never exposed to radiation, though it traveled with the other three chips between the photonics testing facility and the radiation facility. 
     Photonic sensors were irradiated with γ-rays in the NIST high-dose dosimetry laboratory. Three  60 Co irradiators were used with dose rates between 0.2 kGy/h and 3.9 kGy/h. Most of the irradiations were done using irradiator number GC207, which contained a nominal activity of 1.76*10 14  Bq on a reference date and delivered an absorbed dose rate to water, determined using alanine dosimetry, of R=1.08 Gy/s on the reference date, with an expanded uncertainty of about 2%. This amounts to a dose rate per  60 Co activity of D=6.12*10 −15  Gy/s/Bq. 
     Monte Carlo simulations were performed and calculated dose to the silicon devices based on measured dose to alanine calibration pellets. A geometry for the GC  220  was created based on the irradiator specification sheet. The 1 cm diameter  60 Co rods were simulated as a single cylindrical shell. Aluminum and steel shells of 2 mm thickness were implemented between sources and exposure chamber. The  60 Co emission spectrum included two 1.25 MeV γ-rays. 
     Two irradiation geometries were simulated—the chamber calibration and chip irradiation, shown in  FIG. 47 , a cross-sectional side-view of the simulated geometry for the calibration pedestal (left) and chip in beaker geometry (right). The radiation absorber material in the model was varied among water, silicon, and silica. The calibration geometry used to transfer calibration from the primary standard of absorbed dose to water included 5-mm diameter alanine pellets stacked inside a polystyrene cylinder (pedestal) of wall thickness 3.7 mm. For the chip irradiation, one chip at a time was placed inside a glass beaker of diameter and wall thickness of 30.5 mm and 1.3 mm, respectively. Although the chip device layer was only a few μm thick, the simulated dose to the chip was averaged over the top 100 μm of the chip, to achieve adequate Monte Carlo statistics. 
     For the calibration geometry, the simulated result was D=6.23·10 −15  Gy/s/Bq, which is 2% higher than the nominal calibrated value. For the chip geometry, the result was D=5.42·10 −15  Gy/s/Bq. The ratio of the calculated dose for the chip geometry to the calibration geometry was 0.870, with a total Monte Carlo uncertainty of about 3%. 
     Scaling the calibrated value for R by the ratio of the calculated D values for the chip geometry to the calibration geometry resulted in a dose rate to the chip of 0.94 Gy/s with an expanded uncertainty of 7% (k=2). 
     An approximate gamma-ray field map was calculated by numerically solving an integral representing the γ-ray flux, F, inside a chamber consisting of a thin, radiating, cylindrical shell, 
                     F   ⁡     (     x   ,   h     )       =       ∫     -     (       L   2     +   h     )           L   /   2     -   h       ⁢           ⁢       ∫   0     2   ⁢   π       ⁢       r         (       r   ⁢           ⁢     cos   ⁡     (   θ   )         -   x     )     2     +       (     r   ⁢           ⁢     sin   ⁡     (   θ   )         )     2     +     z   2         ⁢   d   ⁢           ⁢   θ   ⁢           ⁢   dz                 (   1   )               
wherein L=210 mm is the shell length, r=105 mm is the shell radius, and (x, h) is the test position within the chamber. No interactions were considered. The field map, relative to the value in the center of the chamber, is shown in  FIG. 48  that shows normalized, simulated gamma-ray field, F (x, h)/F (0,0) for cylindrical shell source. Contours represent a change in field of about 2% of the central value. Along the vertical axis of the chamber (x=0), the field changes by −1% at z=±18 mm. Along the midplane of the chamber (h=0), the field changed by +1% at x=±14 mm. The 5 mm positioning accuracy of the chip did not affect absorbed dose beyond the Monte Carlo and calibration accuracy.
 
     Regarding transient charged particle equilibrium (TCPE), a Monte Carlo model was constructed for a version of the chip geometry. A 1.25 MeV γ-ray source was incident from the side of the chip, aligned with the center of the top layer, which was 200 μm thick and was thicker than the actual device layer, but not thick enough to achieve TCPE. Only about 1 out of 50 γ-rays interact with the chip. Of those that do, about 80% produced Compton-scattered electrons that escaped into the air from the top layer. Since there was not an equal energy flux of electrons produced in the air that pass into the top Si layer, TCPE was not achieved. Therefore, the absorbed dose to the chip was not calculated based on the relative linear-energy transfer and density of silicon relative to water. Rather, full Monte Carlo simulations were performed. 
     Example 1 
     Thermometer 
     A thermometer was fabricated using CMOS techniques on a silicon on insulator (SOI) wafer with a 220 nm thick layer of silicon on top of a 2 μm thick buried oxide layer that isolates an optical mode and prevents loss to the substrate. The fabrication of silicon devices was performed through microfabrication and nanofabrication. Masks were made using ultraviolet light at 193 nm for photolithography and were etched to from a waveguide and Bragg coupler. The Bragg coupler provided free space coupling of light in or out of the thermometer at, e.g., 4 dB per Bragg coupler. The thermometer was subjected to thermal oxidation to form a 10 nm thick SiO 2  layer thereon to reduce a surface roughness. 
       FIG. 39  shows a micrograph of the thermometer  365  that included ring resonator  367  and waveguide  366 . The micrograph was acquired by a scanning electron microscope. Ring resonator  367  had 10 μm radius and was separated from waveguide  366  by 130 nm. The thermometer had a free spectral range of 9.2 nm at 1550 nm, Q-factor of 52000, and estimated group index of 4.2. 
     Example 2 
     Temperature Response of Thermometer 
     The thermometer from Example 1 was subjected to thermal response testing. A tunable laser provided input light to the ring resonator. A portion of the input light was picked up from the laser output for wavelength monitoring while the balance of the input light, after passing through the thermometer, was detected by a power meter. The thermometer was mounted on a two-axis stage in a two-stage temperature-controlled enclosure. Input from a platinum resistance thermometer from each stage was fed to an input channel of a proportional-integral-derivative controller that drove a thermoelectric cooler. The first stage minimizes global temperature fluctuations inside the enclosure to ±1 K, and the second stage minimized temperature variations at the thermometer to less than 17 mK over 24 hours. A relative humidity (% RH) inside the enclosure was monitored by a humidity meter. Relative humidity levels were changed inside the enclosure by varying a flow rate of air saturated with water. 
     The wavelength of the input light from the laser was scanned, and the transmission spectrum was recorded. A center frequency of the transmission spectrum was determined. From a calibration curve, the center frequency was converted to temperature. Thereafter, the temperature of the thermometer was changed from 288 K and 306 K. 
     As shown in  FIG. 40B , the thermometer had a resonant frequency that changed with temperature at 77 pm/K, and the thermometer resolved a temperature difference of 1 mK.  FIG. 22  shows a graph of resonance wavelength versus temperature for the thermometer. 
     A second thermometer having a ring resonator with a radius of 11 μm was prepared per Example 1 and subjected to testing. For the second thermometer, a graph of transmission versus wavelength is shown in  FIG. 40B  with a graph of resonance wavelength versus temperature being shown in  FIG. 40B . 
     Example 3 
       FIG. 41A  shows a graph of the resonance wavelength vs. temperature calibration curve for a fiber Bragg grating. 
     Example 4 
       FIG. 41B  shows a graph of the resonance wavelength vs. temperature calibration curve for a fiber Bragg grating. 
     While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation. Embodiments herein can be used independently or can be combined. 
     Reference throughout this specification to “one embodiment,” “particular embodiment,” “certain embodiment,” “an embodiment,” or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of these phrases (e.g., “in one embodiment” or “in an embodiment”) throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, particular features, structures, or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments. 
     All ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. The ranges are continuous and thus contain every value and subset thereof in the range. Unless otherwise stated or contextually inapplicable, all percentages, when expressing a quantity, are weight percentages. The suffix “(s)” as used herein is intended to include both the singular and the plural of the term that it modifies, thereby including at least one of that term (e.g., the colorant(s) includes at least one colorants). “Optional” or “optionally” means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where the event occurs and instances where it does not. As used herein, “combination” is inclusive of blends, mixtures, alloys, reaction products, and the like. 
     As used herein, “a combination thereof” refers to a combination comprising at least one of the named constituents, components, compounds, or elements, optionally together with one or more of the same class of constituents, components, compounds, or elements. 
     All references are incorporated herein by reference. 
     The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. “Or” means “and/or.” Further, the conjunction “or” is used to link objects of a list or alternatives and is not disjunctive; rather the elements can be used separately or can be combined together under appropriate circumstances. It should further be noted that the terms “first,” “second,” “primary,” “secondary,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity).