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Silicon photonic spectrometer with multiple customized wavelength bands

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Photonics Research 2024年第5期12卷 1016-1023页

作者： LONG ZHANG XIAOLIN YI DAJIAN LIU shiHAN HONG GAOPENG WANG HENGZHEN CAO yaocheng shi DAOXIN DAI State Key Laboratory for Modern Optical Instrumentation Center for Optical&Electromagnetic ResearchCollege of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityZjingang CampusHangzhou 310058China Intelligent Optics and Photonics Research Center Jiaxing Research InstituteZhejiang UniversityJiaxing 314000China Ningbo Research Institute Zhejiang UniversityNingbo 315100China

A silicon photonic spectrometer with multiple customized wavelength bands is developed by introducing multiple channels of wideband optical filters based on multimode waveguide gratings(MWGs)for pre-filtering and the corresponding thermally tunable narrowband filter for high *** these multiple customized wavelength bands,the central wavelengths,bandwidths,and resolutions are designed flexibly as desired,so that the system is simplified and the footprint is minimized for several practical applications(e.g.,gas sensing).A customized silicon photonic spectrometer is designed and demonstrated experimentally with four wavelength bands centered around1310 nm,1560 nm,1570 nm,and 1930 nm,which is,to the best of our knowledge,the first on-chip spectrometer available for sensing multiple gas components like HF,CO,H_(2)S,and CO_(2).The spectral resolutions of the four wavelength bands are 0.11 nm,0.08 nm,0.08 nm,and 0.37 nm,*** a customized silicon photonic spectrometer shows great potential for various applications,including gas monitors,wearable biosensors,and portable spectral-domain optical coherence tomography.

关键词： waveguide bands multiple

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国有企业工资溢价与形成机制

经济理论与经济管理 2024年第7期44卷 72-85页

作者：宋扬石曜丞周广肃中国人民大学经济学院中国人民大学国有经济研究院中国人民大学劳动人事学院 100872

本文基于三轮中国企业雇主—雇员匹配数据追踪调查(CMEELS)数据,采用分位数回归和反事实分解方法,对2017—2021年国有企业工资溢价及其形成机制进行探究。研究发现:这段时期国企相对于非国企存在工资溢价,工资溢价主要集中在中高收入层... 详细信息

本文基于三轮中国企业雇主—雇员匹配数据追踪调查(CMEELS)数据,采用分位数回归和反事实分解方法,对2017—2021年国有企业工资溢价及其形成机制进行探究。研究发现:这段时期国企相对于非国企存在工资溢价,工资溢价主要集中在中高收入层次上,形成国企工资溢价的主要原因是国企和非国企间的劳动力市场分割。进一步分析表明,在高工资水平上,女性和农村户口持有者等群体在非国有企业受到了工资歧视,因此上述群体中存在较大的国企工资溢价。据此本文建议未来应坚持劳动力市场化改革方向,有针对性地打破国企和非国企之间的劳动力市场分割,加强对就业歧视行为的约束,提高中国劳动力市场运行效率。

关键词：劳动力市场国有企业改革工资溢价就业歧视

On-chip digitally tunable positive/negative dispersion controller using bidirectional chirped multimode waveguide gratings

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Advanced Photonics 2023年第6期5卷 72-82页

作者： Shujun Liu Ruitao Ma Zejie Yu yaocheng shi Daoxin Dai Zhejiang University College of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsState Key Laboratory for Extreme Photonics and InstrumentationHangzhouChina Jiaxing Key Laboratory of Photonic Sensing and Intelligent Imaging JiaxingChina Zhejiang University Jiaxing Research InstituteIntelligent Optics and Photonics Research CenterJiaxingChina Zhejiang University Ningbo Research InstituteNingboChina

A silicon-based digitally tunable positive/negative dispersion controller(DC)is proposed and realized for the first time using the cascaded bidirectional chirped multimode waveguide gratings(CMWGs),achieving positive and negative dispersion by switching the light propagation direction.A 1×2 Mach-Zehnder switch(MZS)and a 2×1 MZS are placed before and after to route the light path for realizing positive/negative *** device has Q stages of identical bidirectional CMWGs with a binary *** the digital tuning is convenient and scalable,and the total dispersion accumulated by all the stages can be tuned digitally from−(2^(Q)−1)D0 to(2^(Q)−1)D_(0) with a step of D_(0) by controlling the switching states of all 2×2 MZSs,where D_(0) is the dispersion provided by a single bidirectional CMWG ***,a digitally tunable positive/negative DC with Q=4 is designed and *** CMWGs are designed with a 4-mm-long grating section,enabling the dispersion D_(0) of about 4.16 ps∕nm in a 20-nm-wide *** dispersion is tuned from−61.53 to 63.77 ps∕nm by switching all MZSs appropriately,and the corresponding group delay is varied from−1021 to 1037 ps.

关键词： silicon photonics dispersion tuning digital tuning multimode waveguide grating

Polyaniline-supported tungsten-catalyzed oxidative deoximation reaction with high catalyst turnover number

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Chinese Chemical Letters 2023年第1期34卷 347-350页

作者： Wen Li Feng Wang yaocheng shi Lei Yu School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Polyaniline-supported tungsten(W@PANI)was easily prepared by immersing polyaniline(PANI)in the aqueous solution of *** was found to be an efficient catalyst for oxidative deoximation reaction,the very important transformation for pharmaceutical *** the green features,the method employed very few of catalytic tungsten(0.048 mol%*** substrates),resulting in the high turnover numbers(TONs)of the catalyst(ca.103 mol/mol)and the low metal residues in product(<0.1 ppm).The reaction is applicable for a variety of substrates,including those containing heterocycles,which are key intermediates in medicine *** has also been successfully magnified to kilogram scale production to afford the desired carbonyl products smoothly.

关键词： Deoximation Carbonyl Tungsten Free radical reaction Oxidation

Toward calibration-free Mach-Zehnder switches for next-generation silicon photonics

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Photonics Research 2022年第3期10卷 793-801页

作者： Lijia Song Tangnan Chen Weixi Liu Hongxuan Liu Yingying Peng Zejie Yu Huan Li yaocheng shi Daoxin Dai State Key Laboratory for Modern Optical Instrumentation College of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityZijingang CampusHangzhou 310058China International Research Center for Advanced Photonics Zhejiang UniversityHaining 314499China

Silicon photonic Mach–Zehnder switches(MZSs)have been extensively investigated as a promising candidate for optical ***,conventional 2×2 MZSs are usually prone to the size variations of the arm waveguides due to imperfect fabrication,resulting in considerable random phase imbalance between the two arms,thereby imposing significant challenges for further developing next-generation N×N *** we propose a novel design toward calibration-free 2×2 and N×N MZSs,employing optimally widened arm waveguides,enabled by novel compact tapered Euler S-bends with incorporated mode *** standard 180 nm CMOS foundry processes,more than thirty 2×2 MZSs and one 4×4 Benes MZS with the new design are fabricated and *** with their conventional counterparts with 0.45-μm-wide arm waveguides,the present 2×2 MZSs exhibit significant reduction in the random phase *** measured extinction ratios of the present 2×2 and 4×4 MZSs operating in the all-cross state are 27-49 dB and∼20dB across the wavelength range of∼60nm,respectively,even without any *** work paves the way toward calibration-free large-scale N×N MZSs for next-generation silicon photonics.

关键词： free calibration thereby

On-chip optical matrix-vector multiplier based on mode division multiplexing

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Chip 2023年第4期2卷 63-70页

作者： Qiaolv Ling Penghui Dong Yayan Chu Xiaowen Dong Jingye Chen Daoxin Dai yaocheng shi State Key Laboratory for Modern Optical Instrumentation Centre for Optical and Electromagnetic ResearchCollege of Optical Science and EngineeringIn-ternational Research Center for Advanced PhotonicsZhejiang UniversityZijin-gang CampusHangzhou 310058China Ningbo Research Institute Zhejiang UniversityNingbo 315100China Huawei Technologies Co. LtdShenzhen 518000China

Published online:14 August 2023 A matrix-vector multiplication(MVM)optical signal processor based on mode division multiplexing(MDM)was proposed and demon-strated in the current work,which is composed of a mode multiplexer,a multimode beam splitter,a mode demultiplexer,a modulator ar-ray and *** addition,the characteristics of MDM obviate the need for multiple wavelengths and therefore multiple laser light sources are unneeded,which greatly reduces the complexity and cost.A 4×4 MDM-MVM was realized on a standard silicon-on-insulator(SOI)*** with the off-chip light source and photode-tectors(PDs),4-level modulation has been demonstrated,and each level of the output signal could represent 2 bits of information.

关键词： Photonic computing Silicon photonics Matrix vector multiplier Mode division multiplexing

基于仿真数据驱动的激光钻进气体喷嘴结构优化

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钻探工程 2024年第3期51卷 69-75页

作者：文国军黄子恒王玉丹史垚城姜宇昊中国地质大学(武汉)机械与电子信息学院湖北武汉430074

激光钻进采用气体作为循环介质进行清孔,合理的气体流动特性是高效清孔的保障,气体喷嘴是影响气体流动特性的直接因素,其结构设计不合理会严重影响激光钻进的效率。针对激光钻进实验平台中的气体喷嘴,构建喷嘴基本型态,对影响气体清孔... 详细信息

激光钻进采用气体作为循环介质进行清孔,合理的气体流动特性是高效清孔的保障,气体喷嘴是影响气体流动特性的直接因素,其结构设计不合理会严重影响激光钻进的效率。针对激光钻进实验平台中的气体喷嘴,构建喷嘴基本型态,对影响气体清孔效率的喷嘴结构尺寸进行分析,制定仿真方案,通过Fluent模拟气体流场,对清孔效果进行分析,采用神经网络分析喷嘴结构及仿真结果,训练神经网络模型,得出最佳清孔效率时的喷嘴结构参数并进行验证,为喷嘴结构设计提供参考。

关键词：激光钻进流体仿真神经网络气体喷嘴清孔

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High-speed 2D beam steering based on a thin-film lithium niobate optical phased array with a large field of view

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Photonics Research 2023年第11期11卷 1912-1918页

作者： WENLEI LI XU ZHAO JIANGHAO HE HAO YAN BINGCHENG PAN ZICHEN GUO XIANG’E HAN JINGYE CHEN DAOXIN DAI yaocheng shi State Key Laboratory for Modern Optical Instrumentation Center for Optical and Electromagnetic ResearchInternational Research Center for Advanced PhotonicsNingbo Research InstituteCollege of Optical Science and EngineeringZhejiang UniversityChina School of Physics Xidian UniversityXi’an 710071China

An on-chip optical phased array (OPA) is considered as a promising solution for next generation solid-state beam ***,most of the reported OPAs suffer from low operating bandwidths,making them limited in many *** propose and demonstrate a high-speed 2D scanning OPA based on thin-film lithium niobate phase modulators with traveling-wave *** measured modulation bandwidth is up to 2.5 ***,an aperiodic array combined with a slab grating antenna is also used to suppress the grating lobes of far-field beams,which enables a large field of view (FOV) as well as small beam width.A 16-channel OPA demonstrates an FOV of 50°×8.6°and a beam width of 0.73°×2.8°in the phase tuning direction and the wavelength scanning direction,respectively.

关键词： optical antenna tuning

Anisotropic metamaterial-assisted all-silicon polarizer with 415-nm bandwidth

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Photonics Research 2019年第12期7卷 1432-1439页

作者： HONGNAN XU DAOXIN DAI yaocheng shi Centre for Optical and Electromagnetic Research State Key Laboratory for Modern Optical Instrumentation Zhejiang UniversityZijingang Campus

Polarizers have been widely used in various optical systems to reduce polarization cross *** polarizers based on the silicon nanowire waveguide can provide chip-scale device size and a high polarization extinction ***,the working bandwidth for the on-chip silicon polarizers is always limited(20 d B)over a>415 nm bandwidth from1.26 to 1.675μm,which is at least fourfold better than what has been demonstrated in all previous *** the best of our knowledge,such a device is the first all-silicon polarizer that covers O-,E-,S-,C-,L-,and U-bands.

关键词： polarization waveguide polarizer