bluuebunny/crossref_metadata_2025 huggingface dataset:
Lidar Observations of Pinatubo Aerosols at Table Mountain (34° N) and their Effect on Ozone DIAL Measurements
Authors: McDermid I. S. , Walsh T. D. , Schmoe M. , Hoff R. , Haner D. A.
Published: February 2023

Stratospheric aerosols resulting from the volcanic eruption of Mount Pinatubo have been observed in lidar measurements at Table Mountain, California (34.4° N, -117.7° W). Two separate lidar systems have been used to make measurements at four different wavelengths; 308 nm, 352 nm, 532 nm, and 1064 nm. A record of the evolution of the stratospheric aerosol loading, in terms of the backscatter ratio, as a function of time and altitude will be presented. The first evidence of the volcanic aerosols was on July 4, 1991, when increased backscattering, centered at approximately 17 km altitude, was observed. Until July 29, 1991, there was no indication of aerosols above 20 km altitude but since then there has been substantial variation and the stratosphere is sometimes essentially clear but on other occasions scattering ratios up to 10 (at 532 nm) have been observed. Large variations in the aerosol scattering have been observed, even on short time scales (10 min).

The presence of these aerosols has a profound effect on the ongoing measurements of stratospheric ozone profiles using the DIAL technique. Corrections for aerosol effects, which have generally been ignored for stratospheric measurements, should be included in the DIAL analysis. It would be useful at this point to obtain as much experimental information as possible concerning the differential scattering and extinction properties of this aerosol for the ozone DIAL wavelengths, otherwise the corrections can only be as good as the model used. Examples of recent results will be used to illustrate the effects. However, even though the ozone measurements are affected in the regions of the aerosol layers they appear to be unaffected in clear regions and ozone measurements up to 50 km altitude are still possible.
Pinatubo Dust Observations from Fairbanks and Boston
Authors: Burka M. , Dao P. D. , Davidson G. , Farley R. , McNutt R. , Meriwether J. W. , Wilson A.
Published: February 2023

Rayleigh lidar observations from Poker Flat, Alaska show the arrival of a dust cloud near 20 km on 12 August 91. Rayleigh and Raman lidar observations from Boston provide a measure of the backscatter ratio of the 20 km dust cloud.
A first look at the cryogenic limb array etalon spectrometer infrared limb emission spectra for selected stratospheric trace species and aerosol
Authors: Roche A.E. , Kumer J.B. , Mergenthaler J.L.
Published: February 2023

Abstract and summary are not available.
WINDII THE WIND Imaging Interferometer on the UARS Mission
Authors: Shepherd Gordon G. , Thuillier Gerard
Published: February 2023

WINDII, the WIND Imaging Interferometer is one of two instruments aboard the Upper Atmosphere Research Satellite mission which are responsible for measuring atmospheric winds. WINDII concentrates on the uppermost part of the altitudes covered by UARS, with a primary emphasis on the range 80 to 110 km, extended at times as high as 300 km. WINDII measures winds by taking advantage of the light emitted from the airglow, both during the day and at night. During the day, the emission is produced primarily by the impact of photoelectrons generated by the absorption of solar EUV radiation. During the night, emissions are mainly produced by the recombination of atomic oxygen, or of molecular ions. The hydroxyl radical is a special case; it is produced by the reaction of H and O3. A range of emissions is used for WINDII in order to cover the full desired altitude range. A summary of the emissions and the altitude range associated with each is given in the following table.
Preliminary Results from the Solar Ultraviolet Spectral Irradiance Monitor (SUSIM) on the Upper Atmosphere Research Satellite (UARS)
Authors: Lean J. L. , VanHoosier M. E. , Brueckner G. E.
Published: February 2023

On Friday 11th October 1991, after one month of outgassing, SUSIM commenced observing the sun near the maximum of activity in cycle 22. Since then, scans of spectral irradiance from 115 to 410 nm have been collected dally with 1 nm and 5 nm resolution, and weekly with 0.15 nm resolution. During the first week of solar observing, SUSIM’s responsivity was calibrated by each of four on-board deuterium lamps. Subsequent calibrations at monthly intervals will provide long term tracking of responsivity changes, enabling real solar variability during the descending phase of the solar cycle to be separated from instrumental degradation effects.
Optical Remote Sensing in the Atmospheric Radiation Measurement Program
Authors: Stokes Gerald M.
Published: February 2023

The Atmospheric Radiation Measurement (ARM) Program is a Department of Energy multi-year effort whose primary goal is the improvement of the quality of general circulation models (GCMs) of the atmosphere which are used for climate prediction. ARM seeks to improve these models through an extensive effort combining observations and basic process modeling. The proper performance of climate prediction models depends on the quality of the representations of the basic atmospheric processes within the model. The processes of most important to the ARM program are radiative transfer under a variety of physical conditions and those processes responsible for the formation, maintenance, and dissipation of clouds. One of the challenges in study of radiative processes, in particular, is the characterization of the state of the atmosphere on a time scale appropriate to radiative processes, essentially instantaneously. Optical remote sensing techniques offer excellent tools for such characterizations. However, many of the algorithms and basic approaches to optical remote sensing depend exactly on the same models and basic data that need to be tested in the radiative transfer codes. The method by which ARM combines optical techniques with other remote sensing techniques offers an interesting set of solutions to this problem.
Ground-based and airborne lidar measurements of atmospheric aerosols
Authors: Uchino Osamu , Mizuno Yoshinari , Takashima Hideaki , Fujimoto Toshifumi , Nagai Tomohiro , Nikaidou Yoshinobu
Published: February 2023

Ground-based lidar measurements of free tropospheric aerosols and stratospheric aerosols have been made since 1982 at Tsukuba (36.1°N, 140.2°E) in Japan. The purposes of aerosol measurements are knowing aerosol variations related with pressure pattern and studying some transport mechanisms of aerosols which are originated from explosive volcanic eruptions, dust storms in China and fires such as the Kuwait’s oil wells.
Intercomparison of Airborne Measurements of Stratospheric Hydrogen Chloride and Hydrogen Fluoride
Authors: Abrams Mark C. , Mankin William G. , Coffey Michael T. , Toon Geoffery C.
Published: February 2023

Two sets of stratospheric trace gas columns obtained during the Airborne Arctic Stratospheric Experiment by Fourier transform infrared absorption spectroscopy differed sufficiently to warrant a reexamination and intercomparison. The intercomparison had three goals: the determination of the source(s) of the discrepancies, the remeasurement of the raw data using a variety of trace gas retrieval methods, and the determination of the errors involved in such measurements. New measurements of the data suggest that the spectra are remarkably consistent, and provide similar vertical columns when analyzed with one set of assumptions and a particular spectrum analysis method. The intercomparison suggests that the absolute value of vertical columns can be altered by changing the model assumptions and the fitting method. Conclusions regarding data intercomparison and methods of data analysis are discussed in the context of future AASE and AAOE missions and the NDSC.
HALOE Observations of Ozone, Halogen, Nitrogen, and Hydrogen Compounds Made from the UARS Platform
Authors: Russell J. M. , Gordley L. L. , Park J. H. , Drayson S. R.
Published: February 2023

The Halogen Occultation Experiment (HALOE) was launched September 12, 1991, by the Space Shuttle Discovery into a 57°, 585-km, near-circular orbit onboard the Upper Atmosphere Research Satellite (UARS). The experiment was allowed to outgass for about 1 month before science observations began on October 11, 1991. The experiment approach is solar occultation. The instrument technique uses the principle of gas-filter radiometry in four channels to measure vertical profiles of HCℓ, HF, CH4, and NO, and broadband radiometry in four other channels to measure NO2, H2O, O3, and CO2. The latter channel is used for pressure registration and temperature versus pressure sounding of the atmosphere. Methane measurements extend to about 70 km, H2O and temperature to 80 km, O3 to 90 km, HCℓ and HF to ≈ 60 km, NO2 to ≈ 55 km, and NO to 120 km altitude. Results from this experiment have provided the first pressure versus latitude cross sections of HCℓ, HF, and NO, including continuous measurements of NO from the upper troposphere, in some cases, to the lower thermosphere. The data set will be used to pursue a number of scientific investigations, including stratospheric photochemistry and dynamics studies, evaluation of the impact of natural versus anthropogenic chlorine sources on total chlorine, the effect of volcanic aerosols on the chemistry, and study of Antarctic processes which occur during the ozone hole development and recovery phases.
Airborne Ozone Measurements with the USEPA UV-DIAL
Authors: Moosmüller H. , Alvarez R. J. , Edmonds C. M. , Turner R. M. , Bundy D. H. , McElroy J. L.
Published: February 2023

A compact airborne down-looking lidar system has been developed at the U. S. Environmental Protection Agency's Environmental Monitoring Systems Laboratory in Las Vegas.1,2This differential absorption lidar (DIAL) is designed to simultaneously measure range-resolved concentrations of ozone (O3) and sulfur dioxide (SO2) in the lower troposphere, together with an indication of the aerosol distribution. The five laser wavelengths (i.e., λI= 277 nm, λ2= 292 nm, λ3= 313 nm, λ4= 319 nm, λ5= 359 nm) are generated via Raman conversion of a focused KrF excimer laser.3
Simulation Space-Based Doppler Lidar Wind Measurements Using Ground-Based Single Shot Observations
Authors: Emmitt G. D. , Dieudonné J. , Wood S.A. , Wood L.
Published: February 2023

Both single-agency and multi-agency efforts are currently underway to put a Doppler lidar wind sounder into space within the next decade. Justification for this ambitious project rests mainly in the universally recognized need to provide direct measurements of the winds as input to both climate studies and forecast models. Expectations of success are based heavily upon ground-based observations as well as a few airborne observations. While the space-based observations will be taken at 5-10 Hz providing samples with a spatial separation of 50 to 70 kilometers within the earth's atmosphere, both the ground-based and airborne observations have been acquired primarily at 20 to 100 hertz providing a shot density of many samples per square meter resolution. Furthermore, many of the wind velocity estimates derived from these ground-based and airborne instruments have been acquired by using a poly-pulse pair technique involving 20 to sometimes 100 pulses. Currently there is very little in the way of data that is acquired in a single shot mode and processed to achieve resolution, both in space and time, that will approximate that which is achievable with a space-based system.
Comparison of HALOE O3 and H2O Observations from UARS with Ground and Balloonborne Measurements
Authors: Russell James M. , Gordley Larry L. , Purcell Patrick N. , Stone Kenneth V.
Published: February 2023

The HALOE experiment was launched on the UARS satellite by the Space Shuttle Discovery at 7:11:04 EDT on September 12, 1991. After allowing for a period of outgassing, HALOE began taking routine science observations on October 11. HALOE uses the experiment approach of solar occultation and the gas filter and broad band radiometer instrument techniques to measure vertical profiles of HCℓ, HF, CH4, NO, NO2, H2O, O3, aerosol, and temperature versus pressure. The measurements cover a broad altitude range from the upper troposphere in some cases to the lower thermosphere in the case of nitric oxide. Latitude coverage provided by the occultation geometry ranges from 80 ° S to 80 °N over the course of one year. The experiment has operated essentially without flaw for more than three years. Instrument stability over this time, as judged by the maximum signal change when viewing the sun exoatmospherically, is ≤ 2 to 3 %.
Flight Results for the Airborne Raman Lidar
Authors: Heaps Wm. S. , Burris John F.
Published: February 2023

The airborne Raman lidar recently completed a series of flight tests aboard a C-130 aircraft operated by the NASA Wallops Flight Facility. The Raman lidar is intended to make simultaneous remote measurements of methane, water vapor, temperature, and pressure. The principal purpose of the measurements is to aid in the investigation of polar phenomena related to the formation of ozone 'holes' by permitting the identification of the origin of air parcels using methane as a tracer.
A compact CO2-lidar system for the detection of atmospheric pollutants
Authors: Stuffler T. , Schrötter H.W.
Published: February 2023

A mobile, tunable CO2-lidar system using the DAS-technique (Differential Absorption Spectroscopy) has been developed at the University of Munich. The system measures path integrated concentrations of atmospheric pollutants on a distance of up to 5 km. It represents a second generation of CO2-lidars at the Ludwig-Maximilians-University in Munich.
Matching Accuracy Degradation Due to MTF Degradation Due to Atmospheric Effect
Authors: Arai Kohei , Terayama Yasunori
Published: February 2023

For DEM estimation with stereo pair of images, a tie point matching is necessary between the two images, Nadir and Off-nadir viewing images. MTF degradations for both Nadir and Off-nadir viewing images are different so that matching accuracy is degraded in accordance with increasing of the off-nadir viewing angle. This proposed paper will discuss a MTF degradation due to atmospheric effect by means of an inverse Monte Carlo simulation together with an associated matching accuracy degradation. Further, a degradation on DEM estimation is also discussed.
N2O Vertical Profiles Retrieved from Ground-based Solar Absorption Spectra Taken at McMurdo Station During Austral Spring of 1989
Authors: Liu Xu , Murcray F. J.
Published: February 2023

N2O can be a tracer of atmospheric air motion due to its long life time. Ground-based FTIR solar spectra contain information on the vertical distributions of N2O due to pressure-broadening of absorption lines. We have combined the Chahine-Twomey' relaxation method with a line-by-line layer-by-layer radiative transfer code to retrieve N2O VMR profiles from ground-based solar absorption spectra. The spectra were taken at McMurdo station during the austral spring of 1989 with a 0.02 wavenumber resolution FTIR spectrometer. Since N2O is released from troposphere and is photolyzed in the stratosphere, the line shape of its absorption is mainly due Lorentz broadening. The 0.02 wavenumber resolution is high enough for us to retrieve N2O VMR profiles up to 25 kilometers. Figure 1 shows a typical observed N2O solar spectrum near 1993.15 wavenumber (solid line) and a calculated spectrum using our profile retrieval program. The best fit is obtained by iteratively adjusting N2O VMR profile according to the formulation of Chahine and Twomey. A contour plot of N2O VMR versus altitude and julian day number is shown in Figure 2. The lower tropospheric N2O VMRs have an average value around 310 ppb. Correlations of the N2O contour with that of temperature shows interesting features of tropospheric and lower stratospheric air motions. We have also compared the total N2O column amounts retrieved from this profile retrieval method and from the PC version of the non-linear least square spectral fitting algorithm (SFIT). The temporal variations of the N2O total column amounts retrieved from two methods show excellent correlation.
Equivalent Filter-Radiometer Brightness Temperatures from a Fourier Transform Spectrometer
Authors: Shaw Joseph A. , Snider Jack B. , Churnside James H. , Jacobson Mark D.
Published: February 2023

The NOAA Environmental Technology Laboratory has operated radiometers in a variety of field experiments. The infrared instruments include a Fourier Transform InfraRed spectro-radiometer (FTIR) that measures spectral radiance from 500 to 2000 cm-1 at 1-cm-1 spectral resolution, and several filter radiometers (Barnes Precision Radiation Thermometer model 5, PRT5) that measure brightness temperature (Tb) in a 1.48-µm-wide (130 cm-1) band centered at 10.7 µm wavelength. The FTIR calibration uses 77-K and 300-K blackbody sources to cover the entire expected range of atmospheric brightness temperatures, while the PRT5 calibration uses a blackbody source whose temperature is varied between 300 K and about 205 K with a bath of alcohol and dry ice. The PRT5 instrument is smaller and easier to operate than the FTIR, but the FTIR has the advantage of a larger calibration range, a broader bandwidth, and a finer spectral resolution. In this paper we show that the FTIR spectral radiances can be converted to PRT5-equivalent brightness temperatures and used to compare the two instruments, correct the uncalibrated cold PRT5 data, and provide PRT5-like data in the absence of a PRT5.
Results and Developments from the JPL-NDSC Lidar Program
Authors: McDermid I. Stuart , Beyerle Georg , Haner David , LeBlanc Thierry , Sirko Eric , Walsh Daniel
Published: February 2023

JPL operates three lidar systems at Table Mountain, California and one at Mauna Loa, Hawaii. Recent results and developments from these systems are presented.
O3 and NO2 total column databases at the Jungfraujoch and Harestua NDSC stations from FTIR and DOAS UV/Visible observations: an update
Authors: De Mazière Martine , Van Roozendael Michel , Demoulin Philippe
Published: February 2023

Remote sensing measurements of total column amounts by spectroscopic techniques heavily rely on spectroscopic parameters for the target and interfering species, and on a priori vertical profile information. This paper discusses recent updates of O3 and NO2 datasets at the Jungfraujoch and Harestua primary and secondary NDSC (Network for Detection of Stratospheric Changes) stations, resp., from high-resolution EHR (Fourier Transform Infrared) and DOAS (Differential Optical Absorption Spectroscopy) UV/Visible observations. The former are direct-sun absorption measurements throughout the day under clear-sky conditions, the latter are zenith-sky scattered light measurements, daily at twilight. At the Jungfraujoch (ISSJ) the latter are performed with a SAOZ instrument since mid-1990; at Harestua, a home-made, NDSC-qualified instrument has been operated since 1993, on a more or less continuous basis. Two FTIR spectrometers, a Bruker IFS 120HR and a home-made FTS are operated on a regular basis at ISSJ; the FTIR database for NO2 starts in 1985.
Retrieval of vertical profiles of ozone by high-resolution FTIR spectra over Rikubetsu, Japan
Authors: Liu X. , Nakajima H. , Murata I. , Kondo Y. , Murcray F. J. , Zhao Y. , Koike M. , Nakane H.
Published: February 2023

Vertical profiles of volume mixing ratios (VMRs) of ozone were retrieved from high resolution, infrared solar absorption spectra taken at Rikubetsu (43.5 °N, 143.8 °E), Japan by a ground-based Fourier-transform infrared spectrometer (FTIR). The VMR profile retrieval is based on an iterative inversion algorithm, which utilizes a multilayer line-by-line calculations. In total, 96 ozone vertical profiles were retrieved from 48 infrared spectra by using two O3 absorption lines near 10 micron spectral region. These profiles were compared with 21 ozonesonde measurements from nearby ozone sounding stations. The two micro-window regions used for O3 profile retrievals are 1146 cm-1 and 1163 cm-1 spectral regions. Averaged discrepancies were less than ±15 % above 8 km for 1146 cm-1 retrievals, while those were less than ±11 % between 16 and 36 km for 1163 cm-1 retrievals. The standard deviation (SD) of averaged discrepancies were less than ±17 % between 16 and 36 km for 1146 cm-1 retrievals, while those were less than ±12 % between 16 and 36 km for 1163 cm-1 retrievals. In general, O3 VMR profile retrieval gives agreements within ±17 % in SD with ozonesonde measurements between 16 and 36 km altitudes.
Atmospheric Properties in the Tropical Pacific from Raman Lidar
Authors: Eichinger William E. , Cooper Daniel , Tellier Larry , Osborne Michael
Published: February 2023

Surface-atmosphere interactions are dynamical processes that have for the first time been observed in four dimensions by a ship-board scanning water vapor Raman lidar. Until recently, critical boundary layer variables such as water vapor have been estimated from time-series data collected by point sensors on buoys, radiosondes, ships, or aircraft. In contrast, the scanning water vapor Raman lidar has been used to evaluate the spatial as well as temporal characteristics of the atmospheric boundary layer (ABL) with resolution previously unavailable to atmospheric researchers. On two oceanic experiments in 1993 and 1996, the Los Alamos National Laboratory (LANL) team made detailed measurements of boundary layer behavior in the Tropical Pacific, relating sea surface temperature (SST) to boundary layer height, latent energy flux, and intermittent convective structures above the ocean surface. The analysis of the data from these experiments are contributing to the body of knowledge focusing upon the complex dynamics within the ocean-atmosphere interface.
A Spectroscopic Database for Satellite Remote Sensing of Chlorofluorocarbons and Their Alternates
Authors: Varanasi P. , Nemtchinov V.
Published: February 2023

In view of the world-wide interest in the remote sensing of chloro-fluoro-carbons (CFC’s), especially CFC-11 (CFCl3) and CFC-12 (CF2Cl2), hydro-chloro-fluoro-carbons (HCFC’s), HCFC-22 (CHFCl2) in particular, the fluorocarbon CF4, the chlorocarbon CCl4, and sulphur hexaflouride (SF6), we have been performing laboratory measurements of the spectral absorption cross-sections needed for the retrieval of the atmospheric vertical mixing ratios and column abudances of these chemicals from data obtained by satellite-based infrared instruments. These chemicals, which possess either a strong ozone-depletion potential or a global-warming potential, or both, have infrared absorption features that do not readily lend themselves to the conventional line-by-line analysis.1,2Therefore, we adapted a novel technique of measuring the absorption cross-section,kν(cm2molecule-1), which is defined askν=(-lnτν)/pξLin terms of the spectral tranmittanceτνat the wavenumberν, temperatureT, and total pressurepalong an optical path of lengthLthrough the absorbing chemical with a mixing ratio ofξin N2(used in place of air without any measurable difference in the measuredkν) directly. Highly accuratekνmeasured in the thermal infrared bands of CFC-11 (CFCl3), CFC-12 (CF2Cl2), HCFC-22 (CHFCl2), and SF6at several (T,p) combinations representing atmospheric layers3have already been presented at the last Topical Meeting of this series.2We present now the significant enhancement that we have produced in the database on cross-sections by extending our earlier measurements to include additional chemicals such as CF4(CFC-14) and CCl4and conditions encountered in the atmosphere at Arctic and Antarctic latitudes. Our data (Figs. 1 and 2), which were obtained at pressures and temperatures given in commonly tabulated atmospheric models3and represent tangent heights in solar occultation type remote sensing observations of the atmosphere as well as conditions encountered in the polar regions, are directly applicable to the analysis of the satellite data. The data were obtained at temperatures between 180 and 295 K using a high-resolution Fourier-transform spectrometer and are free from instrumental distortion, since the spectra were recorded at spectral resolution that was sufficiently high at broadening pressures corresponding to tropospheric and stratospheric layers. Various methods of extending these data to conditions not covered in the experiments will be discussed.
Commercialization of Lidar: What’s Wrong and How Do We Fix It?
Authors: Moody Stephen E.
Published: February 2023

Lidar has been under active development since the mid 1960’s, starting soon after the first demonstration of laser action. During the intervening years, the Lidar research community has established a solid record of technical achievement. Measurements of aerosols, specific gaseous species, pressure and temperature have been made at enormous ranges, into very low density regions of the atmosphere, simultaneous with extremely high spatial and temporal resolution.
Issues with Commercialization of FTIR and UV-DOAS Optical Remote Sensing Systems
Authors: Spellicy Robert L.
Published: February 2023

Fourier Transform Infrared (FTIR) and Ultraviolet Differential Optical Absorption Spectroscopy (UV-DOAS) are now mature technologies that have been available to industry and government for many years. However, their widespread use is just beginning to expand. From their early introduction, these technologies appeared to offer a significant advancement in monitoring capability and they allowed for substantial reductions in operational costs. In spite of this, they have not received widespread acceptance or commercialization. This appears to be due to a number of factors: 1) the lack of formal regulatory acceptance 2) the lack of appropriate protocols for both system operation and data interpretation, 3) the perceived complexity of the instruments, and 4) lack of an organized approach to demonstrating their applicability to monitoring in specific industries. In this paper we look at these issues and outline the current status with regard to current FTIR and UV-DOAS systems.
Integrated Optics with Liquid Crystalline Thin Films
Authors: Knoll Wolfgang
Published: February 2023

Integrated optical techniques, in particular, plasmon surface polaritons (PSP or surface plasmons, for short) and waveguide modes are employed in order to characterize thin films of liquid crystalline materials with respect to their structural and (anisotropic) optical properties.
Nonlinear Optical Properties of Phthalocyanine Copolymers
Authors: Shirk James S. , Flom Steven R. , Lindle J.R. , Bartoli F.J. , Boyle Michael E. , Adkins James D. , Snow Arthur W.
Published: February 2023

The nonlinear optical properties of a random phthalocyanine/urethane copolymer parallel those of analogous phthalocyanines in solution. They are potential nonlinear media for optical limiters.
Polymer Waveguide Applications in Multichip Modules (MCMs) and Board Level Optical Interconnects
Authors: Liu Yue , Bristow Julian , Marta Terry , Bounnak Sommy , Johnson Klein , Liu Yung , Cole Herb
Published: February 2023

Optical backplanes are of increasing interest for commercial and military avionics processors. For such systems that competes on the basis of throughput per unit volume (and/or weight), increased component counts dictates a move from conventional packaging and board assembly technology to chip-on-board or multichip module (MCM) technologies as clock speeds and number of I/Os increase, and greater functionality are being demanded in a given system. Optical interconnects is likely to find its first introduction in such systems where practical density limits are being reached. Such situations include the maximum pin numbers in a manufacturable board-to-backplane connectors, or the maximum number of I/Os can be provided in an MCM.
Collision Induced Hyper-Rayleigh Light Scattering in CCl4
Authors: Kaatz Philip , Shelton David
Published: February 2023

Hyper-Rayleigh and hyper-Raman light scattering (HRS) were among the first nonlinear optical (NLO) phenomena to be investigated both theoretically and experimentally.1,2A revival of interest in this technique has occured as it is a more general method of investigating the second order NLO properties of molecules.3The HRS experiment allows the characterization of molecules having dipolar or octupolar symmetry, in contrast to electric-field induced second harmonic generation (EFISH), in which only species having dipolar symmetry may be probed.4Moreover, if a polarization analysis is made of the scattered light, relative ratios of the components of the second order NLO polarizability tensor may be determined.5,6In this work we report evidence for the collision-induced modulation of HRS. We find that is necessary to consider the intermolecular collision contribution to HRS in order to obtain accurate ratios of the first (β) hyperpolarizability components. Vapor phase HRS measurements are also reported, where the vapor phase intensities are directly compared with the liquid phase intensities. Local field factors are able to correct for the differences between vapor and liquid phases for the intramolecular contribution to HRS.
Novel Nonlinear Optical Polymers for Second Harmonic Generation
Authors: Tsustumi Naoto , Matsumoto Osamu , Sakai Wataru , Kiyotsukuri Tsuyoshi
Published: February 2023

Recently, we have synthesized a new type of NLO phore whose dipole moment is aligned transverse to the main chain backbone, and resultant poled polymer film shows large second harmonic efficiency with its good thermal stability. In this paper, we present the second harmonic generation (SHG) properties of this novel type of NLO polymer material whose dipole moment is aligned transverse to the main chain backbone and compare these properties to those for the polymer with NLO phore in the main chain backbone.
Orientation of the Disperse Red 1 Chromophore Along the Polar Axis in Ferroelectric Liquid Crystals
Authors: Walba David M. , Cobben Peter L. , Dyer Daniel J. , Müller Uwe , Shao Renfan , Clark Noel A.
Published: February 2023

Organic thin films with large second order nonlinear susceptibility χ(2) are of potential utility in fast integrated electro-optic modulators. Ferroelectric liquid crystals (FLCs), possessing a thermodynamically stable polar structure, and therefore non-zero χ(2) with infinite "thermal stability," combined with good processibility on semiconductor substrates, seem to provide an excellent approach to creation of χ(2) thin films. Indeed, we have outlined in detail an approach for achieving useful χ(2) values in FLCs by orientation of the p-nitroaniline unit along the FLC polar axis. [1] This approach was later shown to afford an FLC glass with χ(2) values on the order of 5 pm/V. [2] However, to be most useful for fabrication of integrated electro-optic modulators, χ(2) values on the order of 50 pm/V arc required.
Recent Advances in High Gain Photorefractive Polymers
Authors: Grunnet-Jepsen A. , Moerner W. E.
Published: February 2023

With the discovery of photorefractivity in inorganic crystals in the late sixties [1,2], it was soon realized that the photorefractive (PR) effect had a large potential within the field of nonlinear optics. The versatility of the effect has since been clearly demonstrated by numerous applications ranging from holographic data storage and image processing to Bragg interference filters, optical interconnects, optical tracking systems, and self-pumped phase conjugate mirrors [3]. The class of photoconductive, electrooptic crystals that exhibited the PR effect quickly expanded to include ferroelectric oxides (BaTiO3, LiNbO3), sillenites (Bi12SiO20, Bi12TiO20, Bi12GeO20) and compound semiconductors (GaAs, InP, CdTe), to mention just a few. Recently completely new classes of materials have been proposed based on polymeric materials, organic glasses, and liquid crystals [4-6]. With the advantage of ease of processing, low cost, and high performance, these materials promise to be good candidates for present and future applications.
Optical Limiting and the Potential Role of Organic Materials
Authors: Van Stryland Eric , Dogariu Arthur , Lim Jin Hong , Hagan David J. , Przhonska Olga
Published: February 2023

We will present a brief review of past work on passive sensor protection devices including the materials studied (e.g. semiconductors, organics and ink) and some of the requirements of optical limiting devices. The nonlinear mechanisms potentially useful for optical limiting include nonlinear absorption, nonlinear refraction and nonlinear scattering. We present methods for characterizing nonlinear materials using Z-scan and related techniques and describe ways to differentiate the nonlinear mechanisms. We will specifically discuss two-photon absorption and excited-state absorption (referred to as reverse-saturable absorption), as well as bound electronic n2 and excited-state refraction. We also show how to examine organic thin films using a modified Z-scan with enhanced sensitivity called EZ-scan. The organic materials studied include phthalocyanine and polymethine dyes. The potential of organics for real optical systems remains to be seen. For example, the most promising organic limiting materials are effective over somewhat smaller spectral ranges than desired. Mixing of different materials in solution or solid matrices may extend the spectral range, and potentially extend the dynamic range as well.
Nonlinear-Optical Properties of Bacteriorhodopsin in Multilayer Langmuir-Blodgett Films
Authors: Kir'yanov A.V. , Lemmetyinen H. , Maslyanitsin I.A. , Suvranskii V.V. , Tkachenko N.A.
Published: February 2023

Nonlinear optical properties of multilayer Langmuir-Blodgett films (LBF) of bacteriorhodopsin (bR) were studied experimentally. The samples were deposited in Y- and Z-configurations (Z-type bR films up to 50 layers were manufactured at first). The method of second-harmonic generation and the Z-scan technique were used in order to evaluate the elements of susceptibility second-order tensor and to determine the sign and approximate magnitude of refractive index nonlinear part for the samples studied.
A Review of Spectacle Lens Design
Authors: Atchison David A.
Published: February 2023

For the purpose of this review, spectacle lens design refers to the design of lenses in order to minimise side-effects of wearing corrective spectacle lenses. These side effects include: aberrations which reduce image quality; factors affecting spatial perception such as spectacle magnification, distortion and visual field size; weight; poor cosmesis.
Image Quality Evaluation of Multifocal Intraocular Lenses
Authors: Silberman Donn Michael
Published: February 2023

Theoretical evaluation includes computer ray traces providing spot diagrams, MTF and MTF through-focus-response (TFR) graphs, and lens efficiency data. Laboratory testing began with modified resolution benches and progressed to automated MTF, MTF TFR, and lens efficiency evaluation of the IOLs in an eye model. Photography through the eye model gives an added perspective on the optical performance of IOLs that is easily interpreted.
Confocal Microscopy of the Cornea
Authors: Koester Charles J.
Published: February 2023

The combination of a high numerical aperture contact objective and a scanning slit confocal microscope has made possible the detailed visualization of keratocytes, basal epithelial cells, and corneal nerves in vivo.
Highly Excited Vibrational States of Molecules by Photoacoustic Spectroscopy and the Local Mode Model
Authors: Fang Howard L. , Swofford Robert L.
Published: February 2023

Gas-phase intracavity cw dye laser photoacoustic spectroscopy has been used to characterize the highly excited overtones of X-H stretching vibrations (X = C, O, N) in molecules. We report here the overtone studies of homologous series of alkenes, alcohols, ketones, nitriles, ethers and amines measured with intracavity photoacoustic technique in the gas phase and supplemented by thermal lensing spectroscopy in the liquid phase.
Photoacoustic Cell Design for the IBM 9600 FTIR Instrument
Authors: McClelland J. F. , Iles M. K. , Kniseley R. N. , Casper J. M.
Published: February 2023

A recently acquired IBM 9600 FTIR spectrometer is being equipped for photoacoustic measurements on condensed samples. A photoacoustic cell, designed for use in the instrument, has a number of important features to enhance the signal to noise ratio and optimize utility.
Photoacoustic Determination of Total Carbon Deposits
Authors: Pleil Joachim D. , Russwurm George M. , McClenny William A.
Published: February 2023

Carbonaceous particles, a major constituent of submicron atmospheric aerosols, have been related to visibility degradation and adverse health effects. Various efforts based on thermal combustion, optical transmittance, nuclear excitation, solid phase photoacoustics and wet chemistry have been made to develop analytical methods to determine elemental and organic carbon, and total carbon values.(1) The technique described here is applied only to total carbon measurements and utilizes a three step process consisting of: 1) carbon combustion to CO2, 2) cold trap preconcentration and 3) gas phase photoacoustic detection. The primary design criteria for this system are simplicity and low cost rather than high precision and low detection limit.
Hardware and Software of Single-Board Correlators
Authors: Labko V.I. , Nikitin V.V. , Nikolaenko G.L. , Yudin I.K.
Published: February 2023

A multi-channel real-time correlator is the most important unit of a photon correlation spectrometer. Correlator design defines basic possibilities and the cost of spectrometer. Modern level of electronics allows to design single-board correlators, plugged into a standard IBM computer. We have created and now manufacture a number of single-board correlators. Precision correlator (8-bits, 72-216 channels, minimal real sample time 50 ns) includes multiple-tau mode, base-line channels, cut of dust mode. It is based on specific CMOS IC designed on our scheme. We also manufacture several simpler versions (4-bit and 1-bit) for industrial applications and university labs. Our devices are used for study of phase transitions and critical phenomena in liguid crystals and surfactant solutions. Moreover, the correlators are used in several research and industrial laboratories in some non-trivial cases: dark suspensions, biological non-transparent solutions, etc.. Many applications demand the analysis of particle size distribution (PSD). We usually use modified cummulant method with original fitting procedure. We studied various PSD analysis methods including inverse Laplace transform, regularization and eigen function methods. Theoretically the ideally (without errors) measured auto-correlation function (ACF) contains full information about PSD. Real ACF has experimental errors within 0.1-1%. In this case some information about PSD will be lost. For measurement accuracy about 0.1% only 3 parameters of PSD are reliable. So, all methods which represent PSD in the form of any function should use some additional assumptions and they do so. These assumptions often do not correspond to reality. As a result the obtained PSD sufficiently differs from the real distribution. Cummulant method is free from this defect. The distribution parameters obtained by this method are correct.
Light Scattering Spectroscopy: With Applications to Fundamental Problems in Physics, Chemistry, Biology and Engineering
Authors: Benedek George B.
Published: February 2023

The process of light scattering superimposes on an incident "carrier" beam an amplitude and phase modulation which precisely mirrors the scattering fluctuations. Using the photoelectric effect one may detect this carrier modulation by the methods of heterodyne or homodyne demodulation familiar in the radio frequency and microwave domain. We shall review applications of this form of very high resolution optical spectroscopy to diverse problems in Physics, Chemistry, Biology and Engineering.
NASA's Microgravity Technology Programs: A potential for establishing an International Microgravity Technology Program?
Authors: Kierk Isabella
Published: February 2023

This paper will present an overview of the NASA's Microgravity Technology Programs, including program policies and new technology requirements, technology development and transfer activities, and planning and reporting processes. The paper will also address a potential for international collaborations both in microgravity science and in technology development and commercialization programs.
Photon Statistics of Light Scattered by a Liquid Gas Interface
Authors: Lading Lars , Mann J. Adin , Edwards R. V.
Published: February 2023

The photon statistics of light scattered by a surface is investigated. It is shown how the photon correlation function depends on the mode of the light scattering configuration and on the space-time correlation of the surface structure. The uncertainties of the estimated photon correlation are evaluated.
High Electron Mobility Transistors - Their Evolution and Ultimate Speed
Authors: Sakaki H.
Published: February 2023

Physical mechanisms governing the ultimate speed of high-purity heterojunction FETs (HEMTS) are discussed together with a preliminary experiment on a novel velocity modulation transistor.
Carrier-Carrier Interaction and Picosecond Phenomena in Polar Semiconductors
Authors: Lugli P. , Ferry D. K.
Published: February 2023

The effect of carrier-carrier interaction in semiconductors becomes important when high concentrations and short characteristic times are reached. By going to submicron dimensions and picosecond resolutions we are often in such situations. The details of energy and momentum relaxation are then crucial and can be stongly affected by the coulombic scattering among carriers and by the onset of collective phenomena.
High Performance Quarter-Micron-Gate MODFETs*
Authors: Berenz John J.
Published: February 2023

Modulation-doped FETs provide a significant performance advantage over conventional GaAs FETs due to the superior transport properties of the two-dimensional electrons which form the conductive channel in these devices. Table 1 compares the material and device characteristics of different FET devices. At TRW quarter-micron-gate AlGaAs/GaAs MODFETs have been fabricated with cut-off frequencies as high as 80 GHz. These devices exhibit noise figures as low as 2.4 dB at 60 GHz with over 7 dB of associated gain. Power-added efficiencies as high as 42 percent have been achieved at 20 GHz. Figure 1 clearly shows the performance advantage of MODFETs over MESFETs in these RF applications.
Optical Evidence of Charge Accumulation in Double-Barrier Diodes
Authors: Vodjdani N. , Costard E. , Chevoir F. , Thomas D. , Cote D. , Bois P. , Delaitre S.
Published: February 2023

Tunneling is one of the basic quantum mechanical phenomena which play a key role in many ultra thin semiconductor devices. Besides their potential for applications, double barrier heterostructures are also interesting for the understanding of tunneling-based transport processes (1) and their dynamics. Time-resolved photoluminescence (PL) has been used to determine the tunneling escape rate of electrons from a single quantum well through a thin barrier into a continuum (2) and to determine the electric field dependance of this tunneling rate (3). The charge accumulation in the quantum well can be estimated using magnetotunneling (4) or steady-state photoluminescence (5) as recently demonstrated.
Devices for Photonic Switching
Authors: Thylén Lars
Published: February 2023

State-of-the art devices for photonic switching are reviewed, emphasizing the time and space switching areas.
Characterization of High-Speed Electrodes for LiNbO3 Electro-Optic Switch Arrays
Authors: Nordin R. A. , Ratajack M. T.
Published: February 2023

High speed lossy electrodes for LiNbO3based electro-optic switch arrays display superior performance when unterminated, as compared to properly terminated electrodes. The electrodes are designed to be sufficiently lossy to attenuate the high frequency ringing resulting from the lack of a load termination. This configuration has several advantages over conventional traveling wave electrodes normally used in high speed electro-optic modulators. These advantages include easier routing, less power required from the source, and comparable settling times. This results in electrodes that are well suited for large switch array applications. Experimental measurements of the transmission line parameters (characteristic impedance and propagation constant), crosstalk (electro-magnetic and acoustic) and thermal response of test coplanar strip electrodes on LiNbO3supports the integration of these unterminated electrodes into large photonic switch arrays.
4X4 InP Crossbar Switch Array Using the Electro-Optic and Carrier Depletion Effects
Authors: Duthie P J , Shaw N , Wale M J , Moseley A
Published: February 2023

The choice of technology for guided wave optical switches must consider three major issues. Firstly the transparency of the data path will be determined by the waveguide and switch element optical characteristics. Secondly the switching speed of the elements, ranging from mS for optomechanical switches to sub-nS for electro-optical and carrier depletion switches, will be determined by the physical mechanism and by the electrical packaging. Switch speed is of especial importance when high data rates are being switched. These issues have been explored for lithium niobate, leading to the demonstration of a 16×16 guided wave electro-optic space switch [1]. The third issue, the monolithic integration of the optoelectronic circuit elements required for routing control and optical signal conditioning, can only be accomplished using a semiconductor technology.
Optical Railtap Systems for Guided-Wave Optical Interconnections
Authors: Lytel R. , Ticknor A.J. , Van Eck T.E. , Lipscomb G.F.
Published: February 2023

Guided-wave optical interconnections offer many potential benefits for high performance integrated electronic systems1. These include higher packing density, lower noise, lower propagation delay, and the easing of many problems encountered in the design of high-frequency on-and off-module connections. Their major impediment to practical use, apart from being a new, unproven technology with little reliability data, has been the requirement to perform two electrical-optical conversions, one each at the source and receiver ends of the optical line. Most previously proposed schemes for guided-wave interconnects have required one laser or LED per signal. In effect, a multichip carrier, monolithic chip, or fully integrated wafer having thousands of interconnects would necessarily have thousands of lasers as well. For direct laser modulation, the output drivers of a given IC must supply sufficient current to achieve and surpass threshold to drive the line with the required temporal edge. For external modulation, the output drivers must supply a sufficient voltage, usually half-wave, to provide sufficient contrast ratio, again with the required temporal edge.
Optoelectronic Shuffle-Exchange Network for Multiprocessor Architectures
Authors: Haney Michael W.
Published: February 2023

The perfect shuffle (PS) [1] is one of the most studied interconnection patterns for multiprocessor architectures. PS links are coupled to arrays of local 2×2 exchange/bypass switches to form shuffle/exchange networks. These networks perform arbitrary permutations of the elements in multistage interconnection networks for applications such as routing and sorting [2,3]. The PS of a 1-D array results by interleaving the elements of the first half of the array with those of the second half, with the first and last elements remaining unchanged in their position. For example, the PS of the 8 element array, {1,2,3,4,5,6,7,8}, is {1,5,2,6,3,7,4,8}. For a processing element (PE) array of size N, a single stage of a shuffle-exchange network contains a PS of size N followed by N/2 exchange/bypass units. Recently the sufficient number of stages required for an arbitrary permutation was proved to be no greater than 31og(N)-3 [4]. Therefore, the total number of active switches required in such permutation networks grows as Nlog(N). Thus, multistage permutation networks are appropriate for applications in which the number of elements is large enough to preclude the use of a crossbar switch, whose complexity would grow as N2.