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2024 International Conference on Smart Electronics and Communication Systems, ISENSE 2024

作者： Anujan, Titto Jose, Tony vijayan, vismaya Karunya Institute of Technology and Sciences Division of ECE Tamil Nadu Coimbatore641114 India College of Engineering Trivandrum Department of Electronics and Communication Engineering Kerala 695016 India

ISBN: (纸本)9798331528126

The frequency range of terahertz (THz) has shown great promise for optical communication due to its enormous bandwidth and low interference. This review paper provides a thorough analysis of the latest developments and current obstacles in THz optical *** microwave and infrared wavelengths, the terahertz (THz) frequency range has special possibilities for optical communication *** investigates how THz frequencies and optical communication are convergent, emphasising the latter's promise for high-bandwidth, low-latency data transfer. We investigate possible uses of THz optical communication, such as sensing, imaging, and wireless networks, highlighting the revolutionary influence of this new sector on the design of communication systems in the future. © 2024 IEEE.

关键词： Bandwidth

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Conceptual design and simulations for the Detector Array for Energy Measurements Of Neutrons (DAEMON): validation of optical physics simulations

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NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 2024年 1061卷

作者： Bidaman, H. Radich, A. J. Garrett, P. E. Bildstein, v. Ahmed, Z. T. Mashtakov, K. R. Univ Guelph Dept Phys Guelph ON N1G2W1 Canada

The utilization of large-scale neutron detector arrays in future experiments is of vital importance to increase our understanding of beta-delayed neutron emitters. A new device, DAEMON (Detector Array for Energy Measurements Of Neutrons), is being designed for the GRIFFIN decay station at TRIUMF-ISAC. DAEMON will improve the precision on the measurement of the neutron kinetic energy through the use of thin plastic scintillators, SiPMs arrays, and the Time-of-Flight technique, to enhance the current capabilities to study neutron rich nuclei at TRIUMF. The performance and feasibility of the DAEMON array was investigated using the Geant4 package to simulate and optimize the experimental design. To test the optical parameters and models implemented in the Geant4 simulations, a comparison with experimental data from small plastic scintillators combined with SiPM detectors was performed. The simulations reproduce the experimental data very well, including features introduced by summing 2 x 2-SiPM arrays in software. This work lays the foundation for simulations of the full DAEMON array.

关键词： Neutron detection Plastic scintillator array Geant4 TRIUMF

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Electrical stimulation for brighter persistent luminescence

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Light(Science & Applications) 2024年第8期13卷 1590-1601页

作者： Xilin Ma Yuhua Wang Takatoshi Seto Key Laboratory for Special Function Materials and Structural Design of the Ministry of Education National&Local Joint Engineering Laboratory for Optical Conversion Materials and Technology of National Development and Reform CommissionDepartment of Materials ScienceSchool of Materials and EnergyLanzhou UniversityNo.222South Tianshui RoadLanzhouGansu 730000China

An immature understanding of the mechanisms of persistent luminescence(PersL)has hindered the development of new persistent luminescent materials(PersLMs)with increased *** this regard,in-situ direct current(DC)electric field measurements were conducted on a layered structure composed of the SrAl_(2)O_(4):Eu^(2+),Dy^(3+)phosphor,and an *** this study,the photoluminescence(PL)and afterglow properties were investigated with respect to voltage by analyzing the current signal and thermoluminescence(TL)*** intensity of PersL increased due to a novel phenomenon known as“external electric field stimulated enhancement of initial brightness of afterglow”.This dynamic process was illustrated via the use of a rate equation approach,where the electrons trapped by the ultra-shallow trap at 0.022 ev could be transferred through the conduction band during long *** afterglow intensity could reach 0.538 cdm^(-2)at a 6 v electric *** design of an electric field stimulation technique enables the enhancement of the intensity of PersLMs and provides a new perspective for exploring the fundamental mechanics of certain established PersLMs.

关键词： spectroscopy luminescence conduction

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Hybrid refractive-metalens design for imaging applications 14

Hybrid refractive-metalens design for imaging applications

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current developments in Lens design and optical engineering XXIv 2023

作者： Ding, Yijun Stone, Bryan D. Bahl, Mayank Heller, Evan Scarmozzino, Robert Synopsys Inc. 199 S. Los Robles Ave. Suite 400 PasadenaCA91101 United States

ISBN: (纸本)9781510665460

Metalenses can be used as standalone single elements or incorporated as one component of a subassembly that also includes other non-metalens optical elements. Because of the sub-wavelength length scale of the meta-atoms, ray-based methods for analysis and optimization may not be considered appropriate. However, by treating the imparted phase appropriately, ray-based methods can be used to design and analyze optical systems that incorporate one or more metalenses. These methods can be applied to imaging systems or illumination systems composed solely of metalenses, or systems that incorporate a mix of metalenses and conventional refractive, reflective, or diffractive optical elements. There are two pieces of information that are required by the ray trace: i) the ray directions following the metalens, and ii) the amount of energy that the ray carries. The distribution of the meta-atoms in the metalens can be used to determine ray directions and Fourier analysis allows for estimation of the energy carried by the rays. The method relies on having access to the imparted phase (from an EM solver, say) that can be accessed during the ray trace. This approach allows for workflows that are familiar to lens designers—even those without experience designing metalenses—while offering results that are in excellent agreement with more rigorous wave-based analyses. This approach is applicable to both polarization-insensitive and polarization-sensitive designs. In this paper, we discuss the design approach and offer design examples. © 2023 SPIE.

关键词： Polarization

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Challenges using data-driven methods and deep learning in optical engineering 23

Challenges using data-driven methods and deep learning in op...

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Conference on current developments in Lens design and optical engineering XXIII Part of SPIE Optics and Photonics Conference

作者： Buquet, Julie Parent, Jocelyn Lalonde, Jean-Francois Thibault, Simon Univ Laval 2325 Rue Univ Quebec City PQ Canada Immervision 2020 Blvd Robert Bourassa Montreal PQ Canada

ISBN: (纸本)9781510654198;9781510654181

Data driven approaches have proven very efficient in many vision tasks and are now used for optical parameters optimization in application-specific camera design. A neural network is trained to estimate images or image quality indicators from the optical characteristics. The complexity and entanglement of such optical parameters raise new challenges we investigate in the case of wide-angle systems. We highlight them by establishing a data-driven prediction model of the RMS spot size from the distortion using mathematical or AI-based methods.

关键词： Computational optics End-to-End design Wide-angle systems Learning-based PSF estimation Distortion Data-driven optical engineering

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Transfer matrix method-based efficiency enhancement of lead-free Cs3Sb2Br9 perovskite solar cell

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SOLAR ENERGY 2023年第1期259卷 63-71页

作者： Sachchidanand Kumar, Anil Sharma, Pankaj PDPM Indian Inst Informat Technol Adv Semicond Mat & Nanoelect Res Grp Design & Mfg Jabalpur 482005 India PDPM Indian Inst Informat Technol Design & Mfg Dept Elect & Commun Engn Jabalpur 482005 India

This work highlights an efficiency enhancement of a lead-free Cs3Sb2Br9-based perovskite solar cell (PSC) by using the transfer matrix method (TMM). This method calculates the optical parameters such as the absorption profile of each layer, and the total reflection profile at the front surface by considering the coherent and incoherent effect in the layers of the Cs3Sb2Br9-based PSC. The calculation of absorption and reflection is done by using the optical electric field (E-field) intensity. The optical E-field intensity profile leads the calculation of the generation of free charge carriers in the absorbing layer and results in the ideal optical current density Jopt of 24.71 mAcm(-2). Furthermore, the obtained optical parameters after the TMM-based simulation are used to design two different models;'SCAPS model' and 'TMM model', for an electrical simulation using SCAPS-1D software. Finally, the lead-free Cs3Sb2Br9-based PSC using the 'TMM model' obtained an effective electrical performance such as JSC of 17.97 mAcm(-2), vOC of 1.54 v, FF of 74.61%, and PCE of 20.67%, respectively, which encourage for the understanding of the operational mechanism of the PSC and will contribute further efficiency improvement.

关键词： Cs3Sb2 Br-9 Transfer matrix method (TMM) Lead-free SCAPS-1D Perovskite solar cell (PSC) optical current density optical electric field

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Spectrally aligned integration of miniaturized substrate-free thin-film filters for fiber optical networks 14

Spectrally aligned integration of miniaturized substrate-fre...

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current developments in Lens design and optical engineering XXIv 2023

作者： Gehrke, Philipp Rüsseler, Anna K. Hoffmann, Gerd A. Wienke, Andreas Kracht, Dietmar Ristau, Detlev Laser Zentrum Hannover e.V. Hollerithallee 8 HannoverD-30419 Germany Welfengarten 1a HannoverD-30167 Germany Gottfried Wilhelm Leibniz Universität Hannover Welfengarten 1 HannoverD-30167 Germany

ISBN: (纸本)9781510665460

This paper presents the active alignment of miniaturized, substrate-free optical thin-film filters (TFFs) according to the filters’ spectral transfer properties for integration into fiber optical networks. optical TFFs are often designed for a specific narrow angle of incidence (AOI) range. Hence, a sufficient manufacturing precision of the angled photonic components connected to the optical filter is needed. These components then can no longer be used for different scenarios where i.e. the incident angle is changed. Conversely, the individual miniaturized optical filter chips can also vary in specification due to slight inhomogeneities during the production on a large-scale wafer. Therefore, not all filter chips on the wafer meet the demanded specifications at the designed AOI, resulting in a reduced yield. Moreover, it requires a time-consuming separation into different quality classes by measuring single filter chips on the wafer. To maximize the amount of usable chips, a procedure was developed to actively align the chips inside a precision optics assembly system by measuring the transmitted power at different wavelengths while tilting them towards the optical axis. When the optimal angle is found, the chip is glued into the optical network platform. Next to maximizing the yield, the production steps can be reduced because the prior separation into quality classes becomes redundant. Manufacturing tolerances during the thin-film deposition are equalized due to the active spectral alignment on a universal optical platform. With this technique, a more versatile process for TFF integration compared to passively aligned assemblies on fixed angle components is demonstrated. © 2023 SPIE.

关键词： Integration

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Generative design and Digital Manufacturing: Using AI and robots to build lightweight instruments 23

Generative Design and Digital Manufacturing: Using AI and ro...

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Conference on current developments in Lens design and optical engineering XXIII Part of SPIE Optics and Photonics Conference

作者： McClelland, Ryan NASA Goddard Space Flight Ctr Greenbelt MD 20770 USA

ISBN: (纸本)9781510654198;9781510654181

Digital engineering technologies are transforming long-stagnant development processes by applying the tremendous advancements in Information Technology (IT) to classical engineering tasks such as design, analysis, and fabrication of space-flight instrument structures. Generative design leverages developments in Artificial Intelligence (AI) and Cloud computing to enable a paradigm shift in the design process, allowing the engineer to focus on defining the requirements and objectives of the design while AI generates optimized designs which comply with the input requirements. Digital Manufacturing allows these complex lightweight designs to be efficiently manufactured by directly fabricating from the resulting 3D models. The development of these two Digital engineering technologies realizes significant mass savings while simultaneously reducing structure development time from months to days. This paper describes the development of the Evolved Structures process applying these technologies to spaceflight optical instrument structures including an example demonstrating greater than 10x reduction in development time/cost and greater than 3x improvement in structural performance.

关键词： Generative design Digital Manufacturing Topology Optimization Evolved Structures AI

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Solar cell performance enhancement using nanostructures

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MATERIALS SCIENCE AND engineering B-ADvANCED FUNCTIONAL SOLID-STATE MATERIALS 2024年 307卷

作者： Tumram, Priya v. Nafdey, Renuka Kautkar, Pranay R. Agnihotri, S. v. Khaparde, Rohini A. Wankhede, S. P. Moharil, S. v. Amolakchand Mahavidyalaya Dept Phys Yavatmal 445001 India Shri Ramdeobaba Coll Engn & Management Nagpur 440013 India JMT Arts & JJP Sci Coll VMV Commerce Nagpur 440008 India KDK Coll Engn Dept Phys Nagpur 440009 India Rashtrasant Tukadoji Maharaj Nagpur Univ Dept Phys Nagpur 440033 India

The review focuses on the recent developments in nanostructure based solar cell technology. Apart from successfully commercialized crystalline silicon (c-Si) solar cells, various other solar cells have been a topic of research since last few decades because limitations of c-Si solar cells such as cost and low efficiency. Though theoretically predicted solar cells efficiencies by Shockley and Queisser for various solar cells are high, real-world solar cell efficiencies are low due to various factors like spectral mismatch, reflection losses, recombination losses, incomplete absorption, etc. The efforts to enhance solar cell performance by using nanotechnology has facilitated development of altogether new types of devices such as quantum dot and nanowire solar cells. Quantum dot solar cells (QDSC) make use of Quantum dots for absorption of incident solar radiation. optical properties of the quantum dots can be manipulated through adjustment of the bandgap which depends on the size. The bandgap tuning makes QDSC adequate for multi-junction solar cells. QD of numerous semiconductors have been investigated for improving solar cell efficiency by exploiting various regions of the solar spectrum. Use of QDs for absorption of the solar light theoretical efficiency limit of mono-junction, as well as tandem cells can be improved. First principle calculations led to the prediction that the encasing QDs in the intrinsic region can significantly enhance the performance of p-i-n structures. The same logic can be used for the tandem cells as well. Apart from QDs, use of nanowires to attain similar improvement but through increasing the short-circuit current (Isc) has also been explored. On the other hand, the problem of optimizing the open-circuit voltage (voc) is not yet satisfactorily solved in photovoltaic devices based on nanowires. One of the approaches had been to incorporate nanophotonics in the design of a solar cell. This concept could be applied to almost all types of cel

关键词： Nanostructure Quantum dots Nanowires Solar cells Semiconductor

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Passive athermalization of MWIR optical designs utilizing different infrared optical materials 23

Passive athermalization of MWIR optical designs utilizing di...

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Conference on current developments in Lens design and optical engineering XXIII Part of SPIE Optics and Photonics Conference

作者： Kucukcelebi, Doruk Aydemir, Sukru Emre Roketsan Kemalpasa Mahallesi Sehit Yuzbasi Adem Kutlu Soka TR-06780 Ankara Turkey

ISBN: (纸本)9781510654198;9781510654181

In this paper, different optical designs, which are composed of different MWIR optical materials, are utilized for passive athermalization and their performance in athermalization are analyzed. The optical designs are carried out by preserving the athermal property as well as keeping the image quality at higher levels within the working temperature between -40 degrees C and +60 degrees C. The passive athermalization process begins with the calculation of athermalization conditions of candidate material properties. By considering these conditions, athermal material pairs are chosen. To reduce optical aberrations, aspherical surfaces are utilized during the optimization process. At the end of the design phase, the performance of different configurations of athermal optical material pairs, which are enclosed by aluminum alloy housing material, are presented.

关键词： Athermalization infrared optical design optical material pair Mid Wave Infrared (MWIR)

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