检索结果-南通市图书馆

Simulation of random fiber Bragg grating array in polarization-maintaining fiber based on photonic localization effect

在线全文

学校读者我要写书评

暂无评论

optoelectronics Letters 2024年第8期20卷 460-471页

作者： LI Zhihan HE Wei LI Shaode key laboratory of the Ministry of Education for optoelectronic Measurement technology and Instrument Beijing Information Science and Technology University Beijing laboratory of Optical Fiber sensing and System Beijing Information Science and Technology University

Mid-infrared wavelength switchable and dual-wavelength random laser output has many potential applications. A polarization-maintaining random fiber Bragg grating(PMRFBG) array based on the photonic localization effect of longitudinal invariant transverse disorder in fiber structure is proposed, which can be used as random feedback of dual-wavelength and wavelength switchable output of random fiber laser(RFL). The random fiber Bragg grating(RFBG) array was designed on the panda-type polarization-maintaining fiber(PMF), and the two center wavelengths were 2 151.60 nm and 2 152.22 nm, respectively. The RFBG array was designed on the bow tie-type PMF, and the two center wavelengths were obtained, which were 2 153.08 nm and 2 153.96 nm, respectively. The RFBG array with a center wavelength of 2 139.27 nm was designed on single-mode fiber(SMF). The length of individual fiber Bragg grating(FBG) and PMRFBG, the refractive index modulation depth, the number of cascaded gratings, and the distance between gratings have different effects on the full width at half maximum(FWHM) and reflectance of the RFBG and PMRFBG array, but not on the central wavelength, as obtained by simulation using the transmission matrix method. The designed PMRFBG array provides theoretical support for the design of the feedback mechanism of RFL.

关键词： A

同方期刊数据库

Broadband high-efficiency dielectric metalenses based on quasi-continuous nanostrips

在线全文

学校读者我要写书评

暂无评论

Opto-Electronic Advances 2024年第5期7卷 43-51页

作者： Xiaohu Zhang Qinmiao Chen Dongliang Tang Kaifeng Liu Haimo Zhang Lintong Shi Mengyao He Yongcai Guo Shumin Xiao key laboratory of optoelectronic technology and Systems of the Education Ministry of China Chongqing UniversityChongqing 400044China Ministry of Industry and information technology key Lab of Micro-Nano optoelectronic information System Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic SystemsHarbin Institute of TechnologyShenzhen 518055China key laboratory for Micro/Nano optoelectronic Devices of Ministry of Education&Hunan Provincial key laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China

Benefiting from the abrupt phase changes within subwavelength thicknesses,metasurfaces have been widely applied for lightweight and compact optical *** broadband and high-efficiency characteristics are highly attractive for the practical implementation of ***,current metasurface devices mostly adopt discrete micro/nano structures,which rarely realize both merits *** this paper,dielectric metasurfaces composed of quasi-continuous nanostrips are proposed to overcome this *** quasi-continuous nanostrips metasurface,a normal focusing metalens and a superoscillatory lens overcoming the diffraction limit are designed and experimentally *** quasi-continuous metadevices can operate in a broadband wavelength ranging from 450 nm to 1000nm and keep a high power *** average efficiency of the fabricated metalens reaches 54.24%,showing a significant improvement compared to the previously reported metalenses with the same *** proposed methodology can be easily extended to design other metadevices with the advantages of broadband and high-efficiency in practical optical systems.

关键词： broadband high-efficiency metalens sub-diffraction quasi-continuous

High performance and stable pure-blue quasi-2D perovskite light-emitting diodes by multifunctional zwitterionic passivation engineering

在线全文

学校读者我要写书评

暂无评论

Advanced Photonics 2024年第2期6卷 32-40页

作者： Chao Shen Shuyan Fang Jibin Zhang Xiangfei Liang Chenhui Su Jian Qing Wanzhu Cai Yunhan Luo Renqiang Yang Lintao Hou Jinan University College of Physics and Optical Engineering Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy Materials Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials Jinan University College of Physics and Optical Engineering Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Zhengzhou University School of Physics and Microelectronics Key Laboratory of Materials Physics of Ministry of Education Jinan University Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Education Institutes Jianghan University School of Optoelectronic Materials and Technology Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education

Despite the rapid advances of red and green perovskite light-emitting diodes（Pe LEDs）, achieving high brightness with high external quantum efficiency（EQE） remains a challenge for the pure-blue Pe LEDs,which greatly hinders their practical applications, such as white-light illumination and in optical communication as a high-speed and low-loss light source. Herein, we report a high-performance pure-blue Pe LED based on mixed-halide quasi-2D perovskites incorporated with a zwitterionic molecule of 3-（benzyldimethylammonio）propanesulfonate（3-BAS）. Experimental and density functional theory analysis reveals that 3-BAS can simultaneously eliminate non-radiative recombination loss, suppress halide migration, and regulate phase distribution for smoothing energy transfer in the mixed-halide quasi-2D perovskites, leading to the final perovskites with high photoluminescence quantum yield and robust spectrum stability. Thus, the highperformance pure-blue Pe LED with a recorded brightness with 1806 cd m;-2;and a relative higher EQE of 9.25% is achieved, which is successfully demonstrated in a visible light communication system for voice signal transmission. We pave the way for achieving highly efficient pure-blue Pe LEDs with great application potential in future optical communication networks.

关键词： pure-blue PeLEDs quasi-2D perovskite zwitterionic additive visible light communication

AWG-based large dynamic range fiber Bragg grating interrogation system

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

optoelectronics Letters 2024年第3期20卷 129-134页

作者： LI Shufeng YUAN Pei LI Ke LI Ting ZHU Lianqing key laboratory of the Ministry of Education for optoelectronic Measurement technology and Instrument Beijing Information Science&Technology UniversityBeijing 100192China Beijing laboratory of Optical Fiber sensing and System Beijing Information Science&Technology UniversityBeijing 100016China

Arrayed waveguide gratings(AWGs) are extensively employed in fiber Bragg grating(FBG) interrogation systems due to their compact size, lightweight nature, and excellent interrogation performance. The resolution and total measurement range of AWG-based FBG interrogation systems are constrained by the output properties of AWG. We proposed an AWG-based large dynamic range interrogation system. The temperature dependence of AWG is exploited to achieve continuous interrogation. The test results show that the interrogation system has a dynamic range of 28.67 nm, an interrogation accuracy better than 25 pm, and a wavelength resolution of 6 pm.

关键词： fiber waveguide AWG

Liquid Crystal Based Label-Free Optical Sensors forBiochemical Application

在线全文

学校读者我要写书评

暂无评论

Photonic Sensors 2024年第2期14卷 57-88页

作者： Jieyuan TANG Zhibin LI Mengyuan XIE Yunhan LUO Jianhui YU Guojie CHEN Zhe CHEN School of Physics and optoelectronic Engineering Foshan UniversityFoshan 528225China Guangdong-Hong Kong.Macao Joint laboratory for Intelligent Micro-Nano optoelectronic technology Foshan UniversiyFoshan 528225China key laboratory of optoelectronic information and sensing Technologies of Guangdong Higher Education Institutes Jinan UniversityGuangzhou 510632.China Department of optoelectronic Engineering Jinan UniversityGuangzhou 510632China JiHua laboratory Foshan 528200China

Biochemical sensors have important applications in biology,chemistry,and ***,many biochemical sensors are hampered by intricate techniques,cumbersome procedures,and the need for *** the past two decades,it has been discovered that liquid crystals can be used to achieve the optical amplification of biological *** modifying recognition molecules,a variety of label-free biochemical sensors can be ***,biochemical sensors based on the amplification of liquid crystals have become one of the most promising *** paper describes in detail the optical sensing principle of liquid crystals,sensing devices,and optical detection ***,the latest research findings are ***,the challenges and future research directions are discussed.

关键词： Optical sensor biochemistry liquid crystal label-free

Sm^(2+)ions boost ammonia electrooxidation reaction on samarium oxide anode for hydrogen generation in non-aqueous electrolyte

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 5856-5862页

作者： Xingyu Liu Xue Yang Han Sun Zekai Yang Haijun Chen Tianjin key laboratory of optoelectronic Thin Film Devices and technology College of Electronic Information and Optical EngineeringNankai UniversityTianjin 300350China

Ammonia has garnered recognition as a zero-carbon fuel due to its high-density hydrogen storage capacity and its convenience for storage and *** address the challenges associated with the direct usage of ammonia,the development of NH_(3)-to-H_(2)conversion technologies has emerged as a promising and effective ***,we present for the first time that crystallized Sm_(2)O_(3−x)electrodes demonstrate high and stable electrocatalytic activities,including N_(2)evolution rate and Faradaic efficiency,for ammonia electrolysis in a non-aqueous *** was observed that Sm^(2+)ions in samarium oxide play an indispensable role in the ammonia electrooxidation reaction on the ***,the mechanism of ammonia electrooxidation has also been elucidated,laying the foundation for a better understanding of the relationship between local structure and electrochemical properties in order to facilitate research on Pt-free electrocatalysts for the electrolysis of ammonia into H_(2).

关键词： NH_(3)-to-N_(2)conversion ammonia electrooxidation reaction ammonia electrolysis non-aqueous electrolyte samarium oxide

Radiation build-up and dissipation in Raman random fiber laser

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(information Sciences) 2024年第1期67卷 254-260页

作者： Shengtao LIN Zinan WANG Jiaojiao ZHANG Pan WANG Han WU Yifei QI key laboratory of Optical Fiber sensing and Communications University of Electronic Science and Technology of China College of Electronics and information Engineering Sichuan University

Raman random fiber laser(RRFL) is a complex physical system that arises from the distributed Raman amplification and the intrinsic stochasticity of fiber *** analysis of the underlying lightwave kinetics at steady state has been the focus of considerable ***,the transient state,such as the RRFL build-up and dissipation,is particularly important for revealing the lightwave interaction ***,we investigate for the first time the RRFL dynamics at the transient state and track the RRFL temporal and spectral evolution theoretically and ***,with the contribution of random distributed feedback,RRFL build-up exhibits continuous Verhulst logistic growth curves without cavity-related features,which is significantly different from the step-like growth curve of conventional fiber ***,the radiation build-up duration is inversely related to the pump power,and the spectral evolution of the RRFL undergoes two phases,i.e.,from spectral density increase to spectral *** the steady state to the pump switch-off state,the RRFL output power dissipates immediately,and the remaining Stokes lightwave from the Rayleigh scattering will gradually disappear after one round *** work provides new insights into the transient dynamic features of the RRFL.

关键词： random fiber laser stimulated Raman scattering transient phenomenon nonlinear optics łinebreak biological growth dynamics

Multi-sensor multispectral reconstruction framework based on projection and reconstruction

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(information Sciences) 2024年第3期67卷 246-262页

作者： Tianshuai LI Tianzhu LIU Xian LI Yanfeng GU Yukun WANG Yushi CHEN School of Electronics and information Engineering Harbin Institute of Technology Heilongjiang Province key laboratory of Space-Air-Ground Integrated Intelligent Remote sensing

The scarcity and low spatial resolution of hyperspectral images(HSIs) have become a major problem limiting the application of the images. In recent years, spectral reconstruction(SR) has been applied to convert multispectral images(MSIs) with abundant quantities and high spatial resolution into HSIs. With the launch of several new multispectral(MS) satellites with a short repeat period, the simultaneous acquisition of images from multiple MS sensors in the same area is gradually becoming feasible. Unfortunately, existing SR methods only consider the reconstruction of the MSIs of a single sensor without considering using MSIs from different MS sensors to obtain a better construction effect through their complementary bands. However,multi-sensor SR is characterized by two problems: inconsistency in the amplitude information of real multisensor imaging and difficulty in the extraction of the complex correlations of bands from different *** solve these problems, this paper proposes a multi-sensor SR framework based on a two-step approach in which the problems of amplitude inconsistency and band information extraction are solved using an ideal projection network and an ideal multi-sensor SR network, respectively. The effectiveness of the proposed method is verified by experiments on three datasets.

关键词： spectral reconstruction spectral superresolution hyperspectral image multispectral image neural networks multi-sensor

A CNN-SVR model for NO_(2)profile prediction based on MAX-DOAS observations:The influence of Chinese New Year overlapping the 2020 COVID-19 lockdown on vertical distributions of tropospheric NO_(2)in Nanjing,China

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第7期141卷 151-165页

作者： Xin Tian Zijie Wang Pinhua Xie Jin Xu Ang Li Yifeng Pan Feng Hu Zhaokun Hu Mingsheng Chen Jiangyi Zheng information Materials and Intelligent sensing laboratory of Anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China key laboratory of Environmental Optical and technology Anhui Institute of optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China School of Environmental Science and optoelectronic technology University of Science and Technology of ChinaHefei 230026China

In this study,a hybrid model,the convolutional neural network-support vector regression model,was adopted to achieve prediction of the NO_(2)profile in Nanjing from January 2019to March *** the sudden decline in NO_(2)in February 2020,the contribution of the Coronavirus Disease-19(COVID-19)lockdown,Chinese New Year(CNY),and meteorologi cal conditions to the reduction of NO_(2)was ***_(2)vertical column densities(VCDs) from January to March 2020 decreased by 59.05%and 32.81%,relative to the same period in 2019 and 2021,*** the period of 2020 COVID-19,the average NO_(2)VCDs were 50.50%and 29.96%lower than those during the pre-lockdown and post-lockdown pe riods,*** NO_(2)volume mixing ratios(VMRs)during the 2020 COVID-19 lock down significantly decreased below 400 *** NO_(2)VMRs under the different wind fields were significantly lower during the lockdown period than during the pre-lockdown period This phenomenon could be attributed to the 2020 COVID-19 *** NO_(2)VMRs be fore and after the CNY were significantly lower in 2020 than in 2019 and 2021 in the same period,which further proves that the decrease in NO_(2)in February 2020 was attributed to the COVID-19 *** source analysis of an NO_(2)pollution episode during the lockdown period showed that the polluted air mass in the Beijing-Tianjin-Hebei was trans ported southwards under the action of the north wind,and the subsequent unfavorable meteorological conditions(local wind speed of<2.0 m/sec)resulted in the accumulation o pollutants.

关键词： MAX-DOAS CNN-SVR Nitrogen dioxide COVID-19 Chinese New Year Regional transport