Query: Versatile multifunctional photonic components

Candidate papers:

abstract: Looking sharp with metalenses High end imaging lenses have tended to be based on bulk optical components. Advances in fabrication techniques have enabled the development of ultrathin, lightweight, and planar lenses (metalenses) that have unprecedented functionalities. These metalenses have the potential to replace or complement their conventional bulk counterparts. Khorasaninejad and Capasso review the evolution of metalenses, summarizing achievements and applications and identifying future challenges and opportunities. Metalenses can have numerous applications, ranging from cellphone camera modules, to wearable displays for augmented and virtual reality and machine vision, to bio imaging and endoscopy. Science, this issue p. eaam8100 BACKGROUND Future high performance portable and wearable optical devices and systems with small footprints and low weights will require components with small form factors and enhanced functionality. Planar components based on diffractive optics (e.g. gratings, Fresnel lenses) and thin film optics (e.g. dielectric filters, Bragg reflectors) have been around for decades; however, their limited functionality and difficulty of integration have been key incentives to search for better alternatives. Owing to its potential for vertical integration and marked design flexibility, metasurface based flat optics provides a rare opportunity to overcome these challenges. The building blocks (BBs) of metasurfaces are subwavelength spaced scatterers. By suitably adjusting their shape, size, position, and orientation with high spatial resolution, one can control the basic properties of light (phase, amplitude, polarization) and thus engineer its wavefront at will. This possibility greatly expands the frontiers of optical design by enabling multifunctional components with attendant reduction of thickness, size, and complexity. ADVANCES Recent progress in fabrication techniques and in the theory and design of metasurfaces holds promise for this new optical platform (metaoptics) to replace or complement conventional components in many applications. One major advance has been the migration to all dielectric metasurfaces. Here, we discuss the key advantages of using dielectric phase shifting elements with low optical loss and strong light confinement in the visible and near infrared regions as BBs of flat lenses (metalenses) High numerical aperture metalenses that are free of spherical aberrations have been implemented to achieve diffraction limited focusing with subwavelength resolution, without requiring the complex shapes of aspherical lenses. Achromatic metalenses at discrete wavelengths and over a bandwidth have been realized by dispersion engineering of the phase shifters. By suitably adjusting the geometrical parameters of the latter, one can impart polarization and wavelength dependent phases to realize multifunctional metalenses with only one ultrathin layer. For example, polarization sensitive flat lenses for chiral imaging and circular dichroism spectroscopy with high resolution have been realized, and off axis metalenses with large engineered angular dispersion have been used to demonstrate miniature spectrometers. The fabrication of metalenses is straightforward and often requires one step lithography, which can be based on high throughput techniques such as deep ultraviolet and nanoimprint lithography. OUTLOOK In the near future, the ability to fabricate metalenses and other metaoptical components with a planar process using the same lithographic tools for manufacturing integrated circuits (ICs) will have far reaching implications. We envision that camera modules widely employed in cell phones, laptops, and myriad applications will become thinner and easier to optically align and package, with metalenses and the complementary metal oxide semiconductor compatible sensor manufactured by the same foundries. The unprecedented design freedom of metalenses and other metasurface optical components will greatly expand the range of applications of micro optics and integrated optics. We foresee a rapidly increasing density of nanoscale optical elements on metasurface based chips, with attendant marked increases in performance and number of functionalities. Such digital optics will probably follow a Moore like law, similar to that governing the scaling of ICs, leading to a wide range of high volume applications. All dielectric metalenses. (A) Schematic of a dielectric pillar acting as a truncated waveguide for phase shifting the incident light. (B) Top view scanning electron microscopy image of a metalens based on titanium dioxide, with dielectric pillars as BBs. (C) Schematic of an achromatic metalens realized by engineering the dispersive response of its BBs. (D) Schematic of a chiral metalens that spatially separates and focuses light with different helicities. (E) Schematic of a metalens that simultaneously focuses and disperses the incident light. (F) Illustration of the concept of vertically stacking metasurfaces to build miniaturized multifunctional systems. ILLUSTRATIONS: RYAN ALLEN/SECOND BAY STUDIOS Recent progress in metasurface designs fueled by advanced fabrication techniques has led to the realization of ultrathin, lightweight, and flat lenses (metalenses) with unprecedented functionalities. Owing to straightforward fabrication, generally requiring a single step lithography, and the possibility of vertical integration, these planar lenses can potentially replace or complement their conventional refractive and diffractive counterparts, leading to further miniaturization of high performance optical devices and systems. Here we provide a brief overview of the evolution of metalenses, with an emphasis on the visible and near infrared spectrum, and summarize their important features: diffraction limited focusing, high quality imaging, and multifunctionalities. We discuss impending challenges, including aberration correction, and also examine current issues and solutions. We conclude by providing an outlook of this technology platform and identifying promising directions for future research.
author_names: Mohammadreza Khorasaninejad

Federico Capasso
title: Metalenses: Versatile multifunctional photonic components
venue: Science
year: 2017

abstract: A multifunctional, semitransparent photovoltaic device is proposed for harvesting sunlight over a tunable spectral range extending from the UV to the IR. Self assembled monolayers of nanospheres applied to luminescent concentrators provide a photon management architecture, which relies on luminescence and diffraction of light. The light diffraction is tuned by changing the sphere diameter to match the transparency region of the fluorophores. The importance of each optical mechanism is inferred from a systematic experimental investigation of the external quantum efficiency of fabricated devices, and from the calculation of the resulting photocurrent under the AM 1.5 solar spectrum. Compared to the conventional luminescent concentrator, relative photocurrent improvements are shown between 50% and 500% depending on the spectral properties of the device components. It has been demonstrated how to tailor the photovoltaic performances, the color and the degree of transparency of the device to provide a versatile photovoltaic unit for sustainable building integrated applications.
author_names: Angelo Bozzola

Valentina Robbiano

Katia Sparnacci

Giulia Aprile

Luca Boarino

Antonio Proto

Roberto Fusco

Michele Laus

Lucio Claudio Andreani

Davide Comoretto
title: A Multi optical Collector of Sunlight Employing Luminescent Materials and Photonic Nanostructures
year: 2016

abstract: Multilayer metasurfaces (MLMs) represent a versatile type of three dimensional optical metamaterials that could enable ultrathin and multifunctional photonic components. Herein, we demonstrate an approach to readily fabricate MLMs, exploiting a thin film self rolling technique. As opposed to standard layer by layer approaches, all the metasurfaces are defined within a single nanopatterning step, significantly reducing fabrication time and costs. We realize two MLM platforms relying on widely used nanopatterning techniques, namely, focused ion beam and electron beam lithographies. A first example are MLMs comprised of nanohole patterns structured into metal dielectric seed bilayers. The second platform is comprised of vertical stacks of angled plasmonic nanorod arrays separated by thin dielectric layers. Such angled MLMs exhibit a selective response to circularly polarized light, in agreement with previous works relying on layer by layer processes. Our approach can pave the way for the efficient prototyping of novel MLMs, such as devices with varying numbers of layers and configurations that can be fabricated on a single chip.
author_names: Esteban Berm'udez-Urena

Ullrich Steiner
title: Self Rolled Multilayer Metasurfaces
venue: ACS Photonics
year: 2019

abstract: Light sheet fluorescence microscopy has made a substantial imprint in the development of cell biology, anatomical sciences and neurosciences with its superior performance of high speed three dimensional imaging acquisition at high resolution. However, its implementation requires delicate instrumentation, and further extension of its present capability seems limited by current optics systems and techniques. Metasurfaces are presently receiving increased attention for its versatile capacity in constructing multifunctional photonic components with low dimension and high efficiency. Here, we propose and design a dielectric metasurface to realize convenient multiple light sheet illumination. In mathematics, ideal periodic multiple light sheets are the Fourier transform of a series of coherent light waves with discrete angular spatial frequencies, which can be easily generated by the sophisticatedly designed compact yet efficient metasurface. Full wave simulations demonstrate that the diffraction pattern, produ.
author_names: Fenghua Shi

Meng Qiu

Lei Zhang

Edmund Y Lam

Dang Yuan Lei
title: Multiplane Illumination Enabled by Fourier Transform Metasurfaces for High Speed Light Sheet Microscopy
year: 2018

abstract: A simple and versatile one pot sol?gel synthesis of Eu3+ doped nanocrystalline TiO2 and ZrO2 nanomaterials is reported in this paper. It consists of the controlled crystallization of Eu3+ doped TiO2 or ZrO2 nanoparticles from an initial solution containing the metal alkoxide, the lanthanide precursor, a complexing agent and a non complexing acid. The main interest is that it could be extended to different lanthanide ions and inorganic metal oxides to prepare other multifunctional nanomaterials. The characterization by XRD, HRTEM and SAED techniques showed that the TiO2 and ZrO2 crystallization takes place at very low temperatures (60??C) and that the crystallite size can be tailored by modifying the synthetic conditions. The optical properties of the resulting materials were studied by emission spectra and decay measurements. Both Eu3+:TiO2 and Eu3+:ZrO2 samples exhibited long lifetime values after removing organic components 0.7 and 1.3?ms, respectively) but the Eu3+:ZrO2 system is specially promising for photonic applications since its value is longer than some reported for other inorganic or hybrid matrices in which Eu3+ ions are complexed. This behaviour has been explained through an effective dispersion of the lanthanide ions within the ZrO2 nanocrystals.
author_names: Beatriz Fores Julian

Rosa Corberan

Eloisa Cordoncillo

Purificacion Escribano

Bruno Viana

Clement Sanchez
title: One pot synthesis and optical properties of Eu3+ doped nanocrystalline TiO2 and ZrO2
year: 2005

abstract: Methods of structuring materials with submicrometer features in two dimensions have become highly sophisticated. For example, lithographic methods are now capable of carving out several hundred million electronic components on an integrated circuit the width of a fingernail. Extending similar architectures into the third dimension by using these topdown engineering methods is possible only to a limited degree and at great expense. Bottom up chemical methods involving self assembly and templating provide promising alternatives to 3D structures with critical dimensions on the length scale of nanometers to micrometers. One such approach, colloidal crystal templating, is particularly versatile, and has been demonstrated for materials that target applications such as photonic crystals, sensors, power storage devices, artificial bone materials and multifunctional catalysts.1
author_names: Melissa A Fierke

Fan Li

Andreas Stein
title: From Form to Function: Molding Porous Materials in Three Dimensions by Colloidal Crystal Templating
year: 2011

abstract: Previously most of the applications of targeting components have been based on the enhanced permeability and retention effect achieved using folic acid, which consider the side effects of the targeting components to some extent. Herein, we report a new strategy to decorate the surface of MOFs using a pemetrexed (MTA) targeting molecule, affording a new drug delivery system of ALA@UIO 66 NH FAM/MTA (ALA 5 amino levulinic acid and FAM 5 carboxyfluorescein) The confocal microscopy and flow cytometry results showed that ALA@UIO 66 NH FAM/MTA presented a better targeting effect compared to ALA@UIO 66 NH FAM/FA (FA folic acid) and indicated a gradually increasing tendency of the targeting effect with the increasing expression of folate receptors on the tumor cell cytomembrane. Furthermore, the cytotoxicity experiment indicates that the combination of chemotherapy and photodynamic therapy is a more effective therapy model than single chemotherapy and photodynamic therapy. This work demonstrates the first attempt at folic acid antagonist (MTA) modification for NMOFs, providing a new concept for the design of MOFs with folate receptor targeting capacity for clinical applications.
author_names: Ying Pan

Zhidong Luo

Xiaoxiong Wang

Q Chen

Junhao Chen

Yucheng Guan

Dong Liu

Hongjia Xu

Jianqiang Liu
title: A versatile and multifunctional metal organic framework nanocomposite toward chemo photodynamic therapy.
venue: Dalton transactions
year: 2020

abstract: Entangled sources are important components for quantum information science and technology (QIST) The ability to generate high quality entangled sources will determine the extent of progress in this field. Unlike previous schemes, a thin quasi phase matching nonlinear crystal and a dense wave division multiplexing device are used here to build high quality versatile photonic sources with a simple configuration that can be used to perform Hong Ou Mandel interference, time energy entanglement and multi channel polarization entanglement experiments. The measurement results from various quantum optical experiments show the high quality of these photonic sources. These multi functional photonic sources will be very useful in a variety of QIST applications.
author_names: Zhao-huai Xu

Yin-hai Li

Zhiyuan Zhou

Shi-Long Liu

Yan Li

Shi-Kai Liu

Chen Yang

Guangcan Guo

Baosen Shi
title: High quality versatile photonic sources for multiple quantum optical experiments.
venue: Optics express
year: 2020

abstract: By combining microwave solid state devices and photonic technologies an outperforming 50 Watts Transmitter and Receiver Module (TRM) with a very low Noise Figure has been successfully realized at GEM Elettronica. The developed TRM, based on microwave photonic high efficiency conversion, integrates all solid state power amplifiers, limiter, circulator and optical components in an extremely compact design ideal for radar antenna remoting. A 16x 50 Watts microwave photonic TRMs configuration has been developed and tested in order to realize an 800 Watts remote phased array Antenna for high performance 3D Multifunctional X band radar.
author_names: Luca Banchi
title: Multi channel Microwave Photonic link for Antenna remoting in Multifunctional Phased Array Radar
venue: 2020 IEEE Radar Conference (RadarConf20)
year: 2020

abstract: Controlled attachment of photoswitchable molecules to solid surfaces is a promising route for the realization of complex machine like molecular functions. A central next step here is the preparation of adlayers with multiple chemical functions that have defined intermolecular spacings and orientations and interact with each other in a controlled way, resulting in novel advanced system properties. We demonstrate that this is possible using molecular platforms with vertical functional units. Employing molecular components with identical triazatriangulenium based units, we prepared mixed adlayers of platforms carrying a stable photoswitch and bare platforms, platforms with vertical pyridine units, and platforms with metastable switches, respectively. All these mixed layers are highly hexagonally ordered, can be easily varied in composition, and exhibit a stochastic arrangement of the two molecular components.
author_names: Talina R Rusch

Melanie Hammerich

Rainer Herges

Olaf M Magnussen
title: Molecular platforms as versatile building blocks for multifunctional photoswitchable surfaces.
venue: Chemical communications
year: 2019