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4th Optics Young Scientist Summit, OYSS 2020

作者： Zhong, Peng Liang, Yuanda Qin, Zujun Huang, Wei Yin, Shan Guangxi Key Laboratory of Optoelectronic Information Processing Guilin University of Electronic Technology Guilin541004 China

ISBN: (数字)9781510643970

ISBN: (纸本)9781510643963

In this work, a five-band metamaterial absorber (MMA) for temperature sensing application in terahertz region is analyzed. The MMA is composed of three layers. The bottom layer is the metallic film, the middle dielectric layer is the indium antimonide (InSb) and the top layer is the metallic pattern, in which five resonance peaks are generated. With utilizing the dielectric thermo sensitive property of InSb, the resonant absorption is tunable by varying temperature. The electric current on the MMA is investigated to better understand the physical mechanism of the resonances, revealing the resonances attributed to the high-order magnetic resonances. The multi-band absorber is insensitive to the polarization angle, and be with ultrathin thickness of structure. This design of the MMA provides a new approach for electromagnetic stealth, sensing and imaging. © SPIE. Downloading of the abstract is permitted for personal use only.

关键词： iii-V semiconductors

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Overcoming High Frequency Limitations of current-Mode Control Using a Control Conditioning Approach — Part II: Implementation and Hardware

arXiv

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arXiv 2022年

作者： Cui, Xiaofan Avestruz, Al-Thaddeus The Department of Electrical and Computer Engineering University of Michigan Ann ArborMI48109 United States

This article is the second part of a paper series about interference in extremum (i.e., peak or valley) current-mode control, which applies to both fixed and variable switching frequency power converters. Specifically, this part presents three control conditioning methods that mitigate the adverse effect of interference. These methods are new ways to use: (i) slope compensation;(ii) low-pass filtering;and (iii) the phenomenon of comparator-overdrive-delay, for control conditioning. The stability criterion, closed-loop dynamics, and transient performance are derived with mathematical rigor for each method. The design tradeoffs are illustrated, discussed, and compared. The effectiveness of all three methods are demonstrated and validated in hardware using a power converter operating at multi-MHz switching frequencies. Copyright © 2022, The Authors. All rights reserved.

关键词： Comparators (optical)

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optical simulation of iii-v semiconductor nanowires/pedot: Pss-based hybrid solar cells: influence of polymer coating thickness and geometrical parameters on light harvesting and overall photocurrent 2nd

Optical simulation of iii-v semiconductor nanowires/pedot: P...

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2nd International Conference on Energy Systems, Drives and Automations, ESDA 2019

作者： Prashant, D.V. Samajdar, Dip Prakash Sachchidanand Department of Electronics and Communication Engineering PDPM Indian Institute of Information Technology Design and Manufacturing JabalpurMadhya Pradesh482005 India

ISBN: (纸本)9789811550881

Hybrid solar cells (HSCs) can be a new pathway for low-cost, flexible, and high efficiency solar cells. iii-V nanowires (NWs) with sub-wavelength scale dimensions have shown excellent optical and electrical properties, and can be easily fabricated on thin substrates together with polymer materials. In order to obtain optimal design requirements for iii-V NWs/PEDOT: PSS HSCs, optical simulations using finite-difference-time-domain (FDTD) method is performed. To enhance light absorption properties of NWs, the important geometrical parameter, namely the diameter (D) of the NWs is optimized. Further, to maximize short-circuit current density, polymer (PEDOT: PSS) coating thickness on the NWs is optimized. In comparison to NW/air system, optimized PEDOT: PSS-coated NWs have shown better intrinsic anti-reflection properties, broad absorption spectra, and enhanced optical generation rates. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2020.

关键词： Nanowires

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optical Properties of Materials and Their Applications Second edition.

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丛书名： Wiley series in materials for electronic and optoelectronic applications

2020年

作者： edited by Jai Singh.

ISBN: (数字)9781119506058;9781119506065

ISBN: (纸本)9781119506317

Provides a semi-quantitative approach to recent developments in the study of optical properties of condensed matter systems Featuring contributions by noted experts in the field of electronic and optoelectronic materials and photonics, this book looks at the optical properties of materials as well as their physical processes and various classes. Taking a semi-quantitative approach to the subject, it presents a summary of the basic concepts, reviews recent developments in the study of optical properties of materials and offers many examples and applications. optical Properties of Materials and Their Applications, 2nd Edition starts by identifying the processes that should be described in detail and follows with the relevant classes of materials. In addition to featuring four new chapters on optoelectronic properties of organic semiconductors, recent advances in electroluminescence, perovskites, and ellipsometry, the book covers: optical properties of disordered condensed matter and glasses; concept of excitons; photoluminescence, photoinduced changes, and electroluminescence in noncrystalline semiconductors; and photoinduced bond breaking and volume change in chalcogenide glasses. Also included are chapters on: nonlinear optical properties of photonic glasses; kinetics of the persistent photoconductivity in crystalline iii-V semiconductors; and transparent white OLEDs. In addition, readers will learn about excitonic processes in quantum wells; optoelectronic properties and applications of quantum dots; and more.

Covers all of the fundamentals and applications of optical properties of materials
Includes theory, experimental techniques, and current and developing applications
Includes four new chapters on optoelectronic properties of organic semiconductors, recent advances in electroluminescence, perovskites, and ellipsometry
Appropriate for materials scientists, chemists, physicists and electrical engineers involved in development o

关键词： Condensed matter Materials Electrooptics

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design and pre-development of an airborne multi-species differential absorption Lidar system for water vapor and HDO isotope, carbon dioxide, and methane observation

Design and pre-development of an airborne multi-species diff...

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2020 International Conference on Space Optics, ICSO 2020

作者： Dherbecourt, J.B. Raybaut, M. Melkonian, J.M. Hamperl, J. Santagata, R. Dalin, M. Lebat, V. Godard, A. Flamant, C. Totems, J. Chazette, P. Pasiskevicius, V. Heinecke, D. Schäfer, H. Strotkamp, M. Geus, J.F. Rapp, S. Sodemann, H. Steen-Larsen, H.C. DPHY ONERA Université ParisSaclay PalaiseauF-91123 France UMR 8190 CNRS-SU-UVSQ Paris France UMR 1572 CEA-CNRSUVSQ Gif-sur-Yvette France Roslagstullsbacken 21 Stockholm10691 Sweden SpaceTech GmbH Seelbachstr. 13 Immenstaad88090 Germany Fraunhofer Institute for Laser Technology Steinbachstr. 15 Aachen52074 Germany InnoLas Laser GmbH Justus-von-Liebig- Ring 8 Krailling82152 Germany Geophysical Institute University of Bergen Bjerknes Centre for Climate Research Bergen Norway

We report on the current design and preliminary developments of the airborne Lidar Emitter and Multi-species greenhouse gases Observation iNstrument (LEMON), which is aiming at probing H2O and its isotope HDO at 1982 nm, CO2 at 2051 nm, and potentially CH4 at 2290 nm, with the Differential Absorption Lidar method (DIAL). The infrared emitter is based on the combination of two Nested Cavity OPOs (NesCOPOs) with a single optical parametric amplifier (OPA) line for high-energy pulse generation. This configuration is enabled by the use of high-aperture periodically poled KTP crystals (PPKTP), which provide efficient amplification in the spectral range of interest around 2 μm with slight temperature adjustments. The parametric stages are pumped with a Nd:YAG laser providing 200 mJ nanosecond double pulses at 75 Hz. According to parametric conversion simulations supported by current laboratory experiments, output energies in the 40 - 50 mJ range are expected in the extracted signal beam whilst maintaining a good beam quality (M2 © 2021 ESA and CNES

关键词： Carbon dioxide

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Effects of polarized-induced doping and graded composition in an advanced multiple quantum well InGaN/GaN UV-LED for enhanced light technology

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engineering RESEARCH EXPRESS 2022年第1期4卷

作者： Das, Samadrita Lenka, Trupti Ranjan Talukdar, Fazal Ahmed Velpula, Ravi Teja Jain, Barsha Hieu Pham Trung Nguyen Crupi, Giovanni Natl Inst Technol Silchar Dept Elect & Commun Engn Silchar 788010 Assam India New Jersey Inst Technol Dept Elect & Comp Engn Newark NJ 07102 USA Univ Messina BIOMORF Dept I-98125 Messina Italy

In this paper, a light-emitting diode in the ultra-violet range (UV-LED) with multiple-quantum wells (MQWs) of InGaN/GaN is designed and analyzed through Technology Computer-Aided design (TCAD) simulations. The polarization effects in iii-nitride heterojunction and the effects of graded composition in the electron blocking layer (EBL) are exploited to enhance the performance of the proposed UV-LED. It is observed that the effect of graded composition in the EBL helps to enhance the electrical and optical performance of the LED, thereby enabling the achievement of some promising results. The simulation-based results demonstrated that superior internal efficiency and an inferior leakage current are achieved by using a graded Al composition in the EBL rather than a uniform composition. The reported results also confirm the remarkable improvement of the light output power by 17% at similar to 100 mA when using the graded composition and also show a reduction in series resistance leading to more current. Graded Al composition in the EBL results in the enhancement of electroluminescence spectra (i.e., an increase in the peak of the spectral density).

关键词： iii-nitride UV-LED deep-ultra-violet (DUV) electron blocking layer (EBL) multiple quantum wells (MQWs) wide-band gap semiconductor devices

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Link loss analysis for a satellite quantum communication down-link 3

Link loss analysis for a satellite quantum communication dow...

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Conference on Emerging Imaging and Sensing Technologies for Security and Defence V / Conference on Advanced Manufacturing Technologies for Micro- and Nanosystems in Security and Defence iii

作者： Zhang, Chunmei Tello, Alfonso Zanforlin, Ugo Buller, Gerald S. Donaldson, Ross J. Heriot Watt Univ Scottish Univ Phys Alliance Sch Engn & Phys Sci Inst Photon & Quantum Sci Edinburgh EH14 4AS Midlothian Scotland

ISBN: (纸本)9781510638945

The analysis of link loss is one of the first and most important steps for the design of an optical communication system. This is particularly vital in quantum communications systems where the information is encoded at the single photon level, and the quantum optical signal cannot be amplified deterministically. In most cases, the desired quantum bit error rate and secure key rate can only be achieved by minimizing the link attenuation and the background noise level in the quantum communication system. In optical fiber implementations, the transmission distance is inherently limited by the loss per unit distance of the optical fiber, meaning fully global coverage is not readily achievable with the current optical fiber backbone networks. To overcome the terrestrial link limitations for quantum communications, long-distance free-space links, using low-Earth orbit satellites are being proposed and implemented. Due to the optical link length, the main contributors to link losses are geometric loss, atmospheric attenuation, and losses associated with pointing and tracking errors. The total link loss is dominated by the geometric loss, therefore, it is important to analyze its importance in relation to the quantum communications link. In this paper, the loss of a low-Earth orbit satellite-to-ground (downlink) quantum communication link is analyzed. The analysis includes losses associate with the channel (geometric and atmospheric) and the receiver system. This paper also compares the data of a known satellite quantum communications mission, highlighting trade-offs in investment for satellite platform and optical ground station. Based on the link loss analysis, decoy state BB84 and E91 protocols were chosen to demonstrate the link performance under an example scenario. The work contributes to the design of the optical ground station for a CubeSat mission.

关键词： quantum communication satellite quantum key distribution link analysis quantum technology single-photon detection optical ground station

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From compressive sampling to compressive tasking:retrieving semantics in compressed domain with low bandwidth

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PhotoniX 2022年第1期3卷 177-198页

作者： Zhihong Zhang Bo Zhang Xin Yuan Siming Zheng Xiongfei Su Jinli Suo David J.Brady Qionghai Dai Department of Automation Tsinghua University100084 BeijingChina Research Center for Industries of the Future and School of Engineering Westlake University310024 HangzhouChina Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province Westlake University310024 HangzhouChina Computer Network Information Center Chinese Academy of Sciences100190 BeijingChina University of Chinese Academy of Sciences 100049 BeijingChina Wyant College of Optical Sciences University of ArizonaAZ 85721 TucsonUSA

High-throughput imaging is highly desirable in intelligent analysis of computer vision *** conventional design,throughput is limited by the separation between physical image capture and digital post *** imaging increases throughput by mixing analog and digital processing through the image capture ***,recent advances of computational imaging focus on the“compressive sampling”,this precludes the wide applications in practical *** paper presents a systematic analysis of the next step for computational imaging built on snapshot compressive imaging(SCI)and semantic computer vision(SCV)tasks,which have independently emerged over the past decade as basic computational imaging *** is a physical layer process that maximizes information capacity per sample while minimizing system size,power and *** is an abstraction layer process that analyzes image data as objects and features,rather than simple pixel *** current practice,SCI and SCV are independent and *** concatenated pipeline results in the following problems:i)a large amount of resources are spent on task-irrelevant computation and transmission,ii)the sampling and design efficiency of SCI is attenuated,and iii)the final performance of SCV is limited by the reconstruction errors of *** these concerns in mind,this paper takes one step further aiming to bridge the gap between SCI and SCV to take full advantage of both *** reviewing the current status of SCI,we propose a novel joint framework by conducting SCV on raw measurements captured by SCI to select the region of interest,and then perform reconstruction on these regions to speed up processing *** use our recently built SCI prototype to verify the *** results are presented and the prospects for a joint SCI and SCV regime are *** conducting computer vision tasks in the compressed domain,we envision that a new era of snapshot compressive imaging wit

关键词： Snapshot compressive imaging Semantic computer vision Computational imaging Deep learning

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Numerical investigation on stress intensity around Bone-Implant interface by 3-Dimensional FEA and experimental verification by optical technique

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Materials Today: Proceedings 2021年 39卷 35-41页

作者： Pankaj Dhatrak Uddhav Shirsat S. Sumanth Vijay Deshmukh School of Mechanical Engineering Dr. Vishwanath Karad MIT-WPU (Formerly MAEER’S MIT) Pune 38 India Department of Mechanical Engineering Bhivarabai Swanat College of Engineering & Researach Pune 41 India Department of Periodontic M. A. Rangoonwal College of Dental Science and Research Centre Pune 01 India International Clinical Dental Research Organisation Pune 38 India

The aim of the current study is to examine numerically the stress intensity along bone-implant interface for selected implant systems under occlusal load using finite element analysis (FEA) and confirming the result experimentally by optical technique. To see the biomechanical performance at bone-implant interface the five types of implant systems are chosen for the current study. A three-dimensional (3D) computer aided design (CAD) is prepared using CreO Parametric modeling software. A non-linear contact between implant and surrounding bone is defined to analyze the stress intensity in the cancellous bone under the applied load of 100 N axial directions, 40 N laterals (Bucco-lingual) direction and 100 N oblique at 45 degree to the longitudinal axis of implant. An experimental photoelastic technique (optical technique) is used to predict the stress intensity in a cancellous bone near the bone-implant interface using Tardy’s method of compensation. A homogeneous blend of Araldite and hardener material is used to prepare a photoelastic block model. The maximum value of stress intensity is noted in Type-I implant system at apical part of implant whereas minimum value was noted in Type-iii implant system under lateral and oblique loads. Stress intensity in cancellous bone at the bone interface is found to be more significant to the applied oblique load.

关键词： Cancellous bone Dental Implant FEA optical Technique Photoelastic stress

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optical Model of Thermal Radiation Loading System for Turbine Vane Leading Edge

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ENERGIES 2021年第24期14卷 8543页

作者： Meng, Xian-long Liu, Cun-liang Zhang, Pu Northwestern Polytech Univ Sch Power & Energy 1 Dongxiang Rd Xian 710072 Peoples R China Northwestern Polytech Univ Shaanxi Key Lab Thermal Sci Aeroengine Syst Xian 710129 Peoples R China Northwestern Polytech Univ Yangtze River Delta Res Inst NPU Taicang 215400 Peoples R China

With the increase of combustion temperatures, the thermal radiation effect for hot components in the new generation of aero-engines has become a key factor in the combustion process, cooling structure design, and thermal protection. A radiation loading system can be used as an external heat source to simulate the real thermal environment of hot components in aero-engines. Total receiving power, as well as 3-D heat flux distribution, should better coincide with real conditions. With the aid of freeform optics and the feedback optimization method, the current study develops a concentrating-type radiation heating system fit for the leading-edge surface of a C3X turbine vane. A xenon lamp combined with a freeform reflector was optimized for controllable heat flux. A design method in the area of illumination engineering was innovatively extended for the current model. Considering the effect of polar angular radiative flux distribution of a xenon lamp, a Monte Carlo ray tracing (MCRT) method was adopted to evaluate the optical performance. Feedback modifications based on Bayesian theory were adopted to obtain the optimal shape of the FFS for target heat flux. The current study seeks a feasible way to generate 3-D heat flux distribution for complex curved surfaces, such as turbine vane surfaces, and helps to simulate the real thermal environment of hot components in aero-engines.

关键词： freeform optics optical concentrator MCRT inverse problem optimization xenon lamp

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