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Ultracompact and multifunctional integrated photonic platform

SCIENCE ADVANCES 2024年第25期10卷 eadm7569页

作者： Du, Zhuochen Liao, Kun Dai, Tianxiang Wang, Yufei Gao, Jinze Huang, Haiqi Qi, Huixin Li, Yandong Wang, Xiaoxiao Su, Xinran Wang, Xingyuan Yang, Yan Lu, Cuicui Hu, Xiaoyong Gong, Qihuang Peking Univ Beijing Acad Quantum Informat Sci Nanooptoelectron Frontier Ctr State Key Lab Mesoscop PhysCollaborat Innovat Ctr Beijing 100871 Peoples R China Peking Univ Beijing Acad Quantum Informat Sci Nanooptoelectron Frontier Ctr Dept PhysCollaborat Innovat Ctr Quantum MatterMi Beijing 100871 Peoples R China Beihang Univ Sch Instrumentat & Optoelect Engn Beijing 100191 Peoples R China Beijing Univ Chem Technol Coll Math & Phys Beijing 100029 Peoples R China Chinese Acad Sci Inst Microelect Beijing 100029 Peoples R China Beijing Inst Technol Sch Phys Key Lab Adv Optoelect Quantum Architecture & Measu Beijing Key Lab Nanophoton & Ultrafine Optoelect S Beijing 100081 Peoples R China Peking Univ Yangtze Delta Inst Optoelect Nantong 226010 Jiangsu Peoples R China Shanxi Univ Collaborat Innovat Ctr Extreme Opt Taiyuan 030006 Shanxi Peoples R China Hefei Natl Lab Hefei 230088 Peoples R China

Realizing a multifunctional integrated photonic platform is one of the goals for future optical information processing, which usually requires large size to realize due to multiple integration challenges. Here, we realize a multifunctional integrated photonic platform with ultracompact footprint based on inverse design. The photonic platform is compact with 86 inverse designed-fixed couplers and 91 phase shifters. The footprint of each coupler is 4 mu m by 2 mu m, while the whole photonic platform is 3 mm by 0.2 mm-one order of magnitude smaller than previous designs. One-dimensional Floquet Su-Schrieffer-Heeger model and Aubry-Andr & eacute;-Harper model are performed with measured fidelities of 97.90 (+/- 0.52) % and 99.34 (+/- 0.44) %, respectively. We also demonstrate a handwritten digits classification task with the test accuracy of 87% using on-chip training. Moreover, the scalability of this platform has been proved by demonstrating more complex computing tasks. This work provides an effective method to realize an ultrasmall integrated photonic platform.

关键词： optical data processing

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Dynamic structures created by asymmetric collisions of half-cycle attosecond pulses in a time-varying resonant medium

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Journal of the optical Society of America B 2025年第7期42卷 1407-1414页

作者： Olga Diachkova Mikhail Arkhipov Nikolay Rosanov Rostislav Arkhipov Ioffe Institute Politekhnicheskaya str. 26 St. Petersburg 194021 Russia Saint Petersburg State University Universitetskaya nab. 7/9 St. Petersburg 199034 Russia o.o.dyachkova@***

Half-cycle attosecond pulses formed from an electromagnetic field half-wave have the shortest duration in a given spectral interval. When these pulses interact coherently with the medium, new types of spatial structures of population inversion may emerge on each resonant transition. Based on numerical calculations, we examine the possibility of ultrafast control of these structures, such as microcavities, in an asymmetric collision of half-cycle pulses in a medium. We demonstrate that it is possible to create dynamic microcavities with controlled parameters, as well as divide the medium into different regions of near-constant population inversion. The selectivity effect is observed, with deeper structures formed on one transition than another, highlighting the possibility of fine-tuning these processes. The results show that time-dependent media could be realized in a conventional resonant medium with discrete energy levels using half-cycle pulses.

关键词： Attosecond pulses Dielectric mirrors High harmonic generation optical data processing Refractive index Whispering gallery modes

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Differential sparse single-pixel imaging with wavelet coefficients 3

Differential sparse single-pixel imaging with wavelet coeffi...

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3rd International Conference on Computer Vision, Image and Deep Learning and International Conference on Computer Engineering and Applications, CVIDL and ICCEA 2022

作者： Wang, Qian Huo, Yaoran Leshan Vocational and Technical College Leshan China Information & Communication Company State Grid Sichuan Electric Power Company Chengdu China

ISBN: (纸本)9781665459112

Wavelet tree-based adaptive compressed ghost imaging has higher imaging speed and better imaging quality than compressed sensing methods. However, the number of samples can be reduced, since finer significant coefficients can be calculated with the existing measurements. This paper proposes a compressive adaptive ghost imaging with block-wise computational sampling in this paper. This method takes full use of the sparsity of the image in the wavelet domain. The block-wise computational sampling computes four LL band coefficients of high resolution via fewer than two measurements. The calculation strategy takes the useful information of the sampled low-resolution coefficients. This brings in fewer measurements. The computed LL band coefficients are also used to sample significant HH, HL, and LH coefficients of the same scale. The extended prediction method can accurately locate the positions of the important coefficients, by eliminating insignificant coefficients that belongs to significant parent coefficient. The simulation results show that the proposed compressive adaptive ghost imaging using block-wise computing sampling can achieve lower rate of sampling and advanced imaging quality. © 2022 IEEE.

关键词： optical data processing

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All-optical graphene-on-silicon slot waveguide modulator based on graphene's Kerr effect

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APPLIED OPTICS 2021年第26期60卷 7945-7954页

作者： Ojaghi, Saleh Golmohammadi, Saeed Soofi, Hadi Islamic Azad Univ Azarshahr Branch Dept Elect Engn Azarshahr Iran Univ Tabriz Fac Elect & Comp Engn Tabriz Iran

All-optical graphene-based optical modulators have recently attracted much attention because of their ultrafast and broadband response characteristics (bandwidth larger than 100 GHz) in comparison with the previous graphene-based optical modulators, which are electrically tuned via the graphene Fermi level. Silicon photonics has some benefits such as low cost and high compatibility with CMOS design and manufacturing technology. On the other hand, graphene has a unique large nonlinear Kerr coefficient, which we calculate using graphene's tight-binding model based on the semiconductor Bloch equations. Its real and imaginary parts are negative at the wavelength of 1.55 mu m and E-F = 0.1 eV. To simultaneously use the benefits mentioned above, we present an all-optical, CMOS-compatible, and graphene-on-silicon slot (GOSS) waveguide extinction and phase modulator that consists of two different geometries. The first one consists of a one-stage GOSS waveguide with a single layer of graphene. To increase the light-graphene interaction and consequently enhance the modulation efficiency (ME), another stage of the GOSS waveguide is placed over the first one. This two-stage configuration is called a graphene-on-silicon double-slot (GOSDS) waveguide. The ME, insertion loss (IL), and modulation depth (MD) for a 12.5 mu m GOSDS waveguide modulator with a double layer of graphene can reach 0.241 dB/mu m, 1.31 dB, and 77%, respectively, at optical pump intensities about 9 MW cm(-2). Our design has a smaller waveguide length (17.6 times) than the previous all-optical graphene-on-silicon ribbon waveguide extinction modulator and high MD (about 2 times) in comparison with a graphene-dad microfiber all-optical extinction modulator. Compared with an all-optical Mach-Zehnder interferometer phase modulator, our design has short graphene coated waveguide length (approximate to 0.1 times) and low local optical intensities (approximate to 0.043 times) needed for pi phase shift. This study may

关键词： Electrooptical modulators optical data processing optical materials Photonic crystals Ultrafast spectroscopy Waveguide modulators

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optical Boundary Reconstruction With Visible Camera in the EXL-50 Spherical Tokamak

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IEEE TRANSACTIONS ON PLASMA SCIENCE 2021年第12期49卷 3848-3852页

作者： Guo, D. Xie, H. S. Bai, W. Liu, W. J. Peng, Y-K M. Song, X. M. Tao, R. Y. Chen, Bo Liu, B. Chen, Bin Deng, B. H. Shi, Y. J. Yuan, B. S. Liu, M. S. Hebei Key Lab Compact Fus Langfang 065001 Peoples R China ENN Sci & Technol Dev Co Ltd Langfang 065001 Peoples R China Taiyuan Univ Technol Coll Elect & Power Engn Taiyuan 030024 Peoples R China

Plasma position and shape parameters are essential for equilibrium control and physics analysis in a tokamak. Such information is often obtained via optical boundary analysis. In this study, a new analysis of the visible image histogram of a high-speed high-resolution camera is presented which can effectively distinguish between the foreground information (showing the plasma of interest) and the background information (showing the inside views of the vacuum vessel wall and flanges, and so on). Using this method, we can obtain a reasonable approximation to the plasma boundary close to the last closed flux surface (LCFS) where plasma brightness contrast is greatest. The reliability and accuracy of this method are checked by comparing it favorably with other algorithms for different plasma shapes. The method is successfully tested also when the outboard plasma boundary oscillates in time with a magnitude of 10%.

关键词： Plasmas Cameras Brightness Image edge detection Calibration optical imaging High-speed optical techniques EXL-50 high-speed camera optical data processing plasma boundary

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Instantaneous Microwave Frequency Measurement using a phase modulator and Gaussian filter based on Photonic Differentiator 2

Instantaneous Microwave Frequency Measurement using a phase ...

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2nd International Conference on Laser, Optics and Optoelectronic Technology, LOPET 2022

作者： Yu, Wenqi Liang, Xiaodong Xing, Guansu Liang, Yu Zhang, Lei Wang, Dongjie Liu, Yandan Liu, Xin Yang, Wanli Ma, Xiang Optical Communication Research and Development Center 54th Research Institute of China Electronics Technology Group Corporation Hebei Shijiazhuang050081 China The 34th Research Institute of China Electronics Technology Group Corporation Guilin541004 China ShijiaZhuang050081 China

ISBN: (纸本)9781510657588

A differentiator-based photonic approach for the instantaneous microwave frequency measurement (IFM) using a phase modulator and an optical Gaussian filter is proposed and experimentally demonstrated. A microwave frequency measurement with high resolution is achieved by a monotonous frequency-to-power mapping obtained by differential operation in optical domain. A proof-of-concept experiment has been performed, in which a measurement error less than ±0.1 GHz over the frequency range 0.1-10 GHz with input power of 0 dBm is demonstrated. The measurement error of the IFM system is still less than ±0.24 GHz, even though input signal power decreases to -30 dBm. The approach suggests a potential capacity for integrated IFM by using all-optical computing. © 2022 SPIE.

关键词： optical data processing

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Dynamic Image-Based Visual Servoing for Quadrotor to Track a Planar Target with Unknown Motion 61

Dynamic Image-Based Visual Servoing for Quadrotor to Track a...

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IEEE 61st Conference on Decision and Control (CDC)

作者： Kumar, Yogesh Roy, S. B. Sujit, P. B. Indraprastha Inst Informat Technol Delhi Dept Elect & Commun Engn Delhi India Indian Inst Sci Educ & Res Bhopal Dept Elect Engn & Comp Sci Bhopal 462066 India

ISBN: (纸本)9781665467612

This paper presents an image-based visual servoing (IBVS) technique for a quadrotor to track a moving planar target having unknown linear and angular velocities. Image moment-based features are derived after transforming the optical measurements to a virtual image plane parallel to the planar target. The kinematic controller is designed incorporating the linear and angular target velocity estimator blocks. The theoretical analysis demonstrates that the errors converge exponentially to an ultimate bound for time-varying target motion and exponentially to zero if the target motion is purely translational with constant velocity. Unlike past literature, the proposed IBVS scheme can handle unknown arbitrary translational and angular (along the z-axis) motions of the target in a unified and model-free manner. Simulation results using circular and Liassajous target motion are provided to validate the efficacy of the proposed scheme.

关键词： optical data processing

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Microscopic analysis of the energy, momentum, and spin distributions in a surface plasmon-polariton wave

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optical MATERIALS EXPRESS 2021年第7期11卷 2165-2191页

作者： Bekshaev, A. Y. Angelsky, O., V Zheng, J. Hanson, S. G. Zenkova, C. Yu II Mechnikov Natl Univ Phys Res Inst Odessa Ukraine Zhejiang Univ Taizhou Res Inst Taizhou Peoples R China Chernivtsi Natl Univ Chernovtsy Ukraine DTU Foton Dept Photon Engn DK-4000 Roskilde Denmark

We analyze the electromagnetic field near a plane interface between a conductive and a dielectric media, under conditions supporting surface plasmon-polariton (SPP) propagation. The conductive medium is described by the hydrodynamic electron-gas model that enables a consistent analysis of the field-induced variations of the electron density and velocity at the interface and its nearest vicinity. The distributions of electromagnetic dynamical characteristics: energy, energy flow, spin and momentum are calculated analytically and illustrated numerically, employing silver-vacuum interface as an example. A set of the "field" and material contributions to the energy, spin and momentum are explicitly identified and classified with respect to their physical origins and properties, and the orbital (canonical) and spin (Belinfante) momentum constituents are separately examined. In this context, a procedure for the spin-orbital momentum decomposition in the presence of free charges is proposed and substantiated. The microscopic results agree with the known phenomenological data but additionally show specific nanoscale structures in the near-interface behavior of the SPP energy and momentum, which can be deliberately created, controlled and used in nanotechnology applications. (c) 2021 optical Society of America under the terms of the OSA Open Access Publishing Agreement Localized light fields attract significant attention due to their impressive abilities within optical nano-probing, precise optical manipulation and optical data processing. Especially, the surface plasmon-polariton (SPP) waves emerging near the interface between dielectric and conductive media are intensively investigated in connection with nano- and micro-optical means for light guiding, switching and controlling, which is crucial for further microminiaturizing of optical information devices and systems [1-6]. Many stimulating and promising applications are related with unique geometro-dynamical properties o

关键词： Electric fields Field enhancement Light fields optical data processing optical fields Surface waves

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Single-shot fringe pattern phase retrieval using improved period-guided bidimensional empirical mode decomposition and Hilbert transform

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OPTICS EXPRESS 2021年第20期29卷 31632-31649页

作者： Goclowski, Pawel Cywinska, Maria Ahmad, Azeem Ahluwalia, Balpreet Trusiak, Maciej Warsaw Univ Technol Inst Micromech & Photon 8 Sw A Boboli St PL-02525 Warsaw Poland UiT Arctic Univ Norway Dept Phys & Technol NO-9037 Tromso Norway

Fringe pattern analysis is the central aspect of numerous optical measurement methods, e.g., interferometry, fringe projection, digital holography, quantitative phase microscopy. Experimental fringe patterns always contain significant features originating from fluctuating environment, optical system and illumination quality, and the sample itself that severely affect analysis outcome. Before the stage of phase retrieval (information decoding) interferogram needs proper filtering, which minimizes the impact of mentioned issues. In this paper we propose fully automatic and adaptive fringe pattern pre-processing technique - improved period guided bidimensional empirical mode decomposition algorithm (iPGBEMD). It is based on our previous work about PGBEMD which eliminated the mode-mixing phenomenon and made the empirical mode decomposition fully adaptive. In present work we overcame key problems of original PGBEMD - we have considerably increased algorithm's application range and shortened computation time several-fold. We proposed three solutions to the problem of erroneous decomposition for very low fringe amplitude images, which limited original PGBEMD significantly and we have chosen the best one among them after comprehensive analysis. Several acceleration methods were also proposed and merged to ensure the best results. We combined our improved pre-processing algorithm with the Hilbert Spiral Transform to receive complete, consistent, and versatile fringe pattern analysis path. Quality and effectiveness evaluation, in comparison with selected reference methods, is provided using numerical simulations and experimental fringe data. (C) 2021 optical Society of America under the terms of the OSA Open Access Publishing Agreement

关键词： Digital holographic imaging Fringe analysis Numerical simulation optical data processing Phase retrieval Spatial frequency

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Scalable optical learning operator

NATURE COMPUTATIONAL SCIENCE

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NATURE COMPUTATIONAL SCIENCE 2021年第8期1卷 542-549页

作者： Tegin, Ugur Yildirim, Mustafa Oguz, Ilker Moser, Christophe Psaltis, Demetri Ecole Polytech Federale Lausanne Opt Lab Lausanne Switzerland Ecole Polytech Federale Lausanne Lab Appl Photon Devices Lausanne Switzerland

Today's heavy machine learning tasks are fueled by large datasets. Computing is performed with power-hungry processors whose performance is ultimately limited by the data transfer to and from memory. Optics is a powerful means of communicating and processing information, and there is currently intense interest in optical information processing for realizing high-speed computations. Here we present and experimentally demonstrate an optical computing framework called scalable optical learning operator, which is based on spatiotemporal effects in multimode fibers for a range of learning tasks including classifying COVID-19 X-ray lung images, speech recognition and predicting age from images of faces. The presented framework addresses the energy scaling problem of existing systems without compromising speed. We leverage simultaneous, linear and nonlinear interaction of spatial modes as a computation engine. We numerically and experimentally show the ability of the method to execute several different tasks with accuracy comparable with a digital implementation.

关键词： optical data processing

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