检索结果-南通市图书馆

Photonics-assisted THz wireless communication enabled by wide-bandwidth packaged backilluminated modified uni-traveling-carrier photodiode

在线全文

学校读者我要写书评

暂无评论

Opto-Electronic Science 2024年第7期3卷 20-29页

作者： Yuxin Tian Boyu Dong Yaxuan Li Bing Xiong Junwen Zhang Changzheng Sun zhibiao hao Jian Wang Lai Wang Yanjun Han Hongtao Li Lin Gan Nan Chi Yi Luo Beijing National Research Center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringFudan UniversityShanghai 200433China Flexible Intelligent Optoelectronic Device and Technology Center Institute of Flexible Electronics Technology of THUJiaxing 314000China

This paper presents a wide-bandwidth back-illuminated modified uni-traveling-carrier photodiode(MUTC-PD)packaged with standard WR-5 rectangular waveguide for high-speed wireless *** optimized epitaxy structure and coplanar waveguide electrodes,the fabricated 4-μm-diameter PD exhibits ultra-flat frequency response and high saturation *** passive circuits including low-loss bias-tee and E-plane probe are designed to package the PD into a compact module with waveguide *** packaged PD module has demonstrated a flat frequency response with fluctuations within±2.75 d B over a broadband of 140–220 GHz and a high saturated output power of-7.8 d Bm(166μW)at 140 *** wireless communication applications,the packaged PD is used to implement 1-m free space transmission at carrier frequencies of 150.5 and 210.5 GHz,with transmission rates of 75 and 90 Gbps,respectively.

关键词： modified uni-traveling-carrier photodiode integrated bias-tee E-plane probe flat frequency response high saturation power WR-5 output THz wireless communications

Advances in neuromorphic computing:Expanding horizons for AI development through novel artificial neurons and in-sensor computing

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第3期33卷 1-23页

作者：杨玉波赵吉哲刘胤洁华夏扬王天睿郑纪元郝智彪熊兵孙长征韩彦军王健李洪涛汪莱罗毅 Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

AI development has brought great success to upgrading the information *** the same time,the large-scale artificial neural network for building AI systems is thirsty for computing power,which is barely satisfied by the conventional computing *** the post-Moore era,the increase in computing power brought about by the size reduction of CMOS in very large-scale integrated circuits(VLSIC)is challenging to meet the growing demand for AI computing *** address the issue,technical approaches like neuromorphic computing attract great attention because of their feature of breaking Von-Neumann architecture,and dealing with AI algorithms much more parallelly and energy *** by the human neural network architecture,neuromorphic computing hardware is brought to life based on novel artificial neurons constructed by new materials or *** it is relatively difficult to deploy a training process in the neuromorphic architecture like spiking neural network(SNN),the development in this field has incubated promising technologies like in-sensor computing,which brings new opportunities for multidisciplinary research,including the field of optoelectronic materials and devices,artificial neural networks,and microelectronics integration *** vision chips based on the architectures could reduce unnecessary data transfer and realize fast and energy-efficient visual cognitive *** paper reviews firstly the architectures and algorithms of SNN,and artificial neuron devices supporting neuromorphic computing,then the recent progress of in-sensor computing vision chips,which all will promote the development of AI.

关键词： neuromorphic computing spiking neural network(SNN) in-sensor computing artificial intelligence

Double-cliff-layer uni-traveling-carrier photodiode with high responsivity and ultra-broad bandwidth

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2024年第5期22卷 100-105页

作者：韩亚茹田雨欣熊兵孙长征王健郝智彪韩彦军汪莱李洪涛甘霖罗毅 Beijing National Research Center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Flexible Intelligent Optoelectronic Device and Technology Center Institute of Flexible Electronics Technology of THUJiaxing 314006China

A novel backside-illuminated double-cliff-layer uni-traveling-carrier(DCL-UTC)photodiode with both high responsivity and ultra-broad bandwidth is designed and demonstrated.A thick absorption layer is adopted for high responsivity,and a depletion region with double cliff layers is proposed to alleviate the space charge effect and maintain overshoot electron velocity under large *** addition,inductive coplanar waveguide electrodes are employed to enhance the frequency response *** 6-μm-diameter photodiode exhibits a high responsivity of 0.51 A/W and a large 3-dB bandwidth of 102 GHz.A high RF output power of 2.7 dBm is recorded at 100 GHz.

关键词： uni-traveling-carrier photodiode high responsivity broad bandwidth

High-speed optoelectronic devices

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2023年第5期66卷 5-27页

作者： Yi LUO Changzheng SUN Bing XIONG Jian WANG zhibiao hao Yanjun HAN Hongtao LI Lai WANG Beijing National Research Center for Information Science and Technology (BNRist) Department of Electronic Engineering Tsinghua University

High-speed optoelectronic devices are key components of modern fiber communication systems,and the backbone of information technology. In this paper, we present our work on high-speed devices over the past decades, including high-performance semiconductor lasers and integrated light sources, wideband electrooptic modulators, high saturation power photodetectors, and their applications in both fiber communications and microwave photonics. Gain-coupled distributed feedback(DFB) lasers were fabricated with high singlemode yield. Electroabsorption modulated lasers(EMLs) were demonstrated based on identical epitaxial layer integration scheme, including single channel 40 Gb/s EMLs, and 4 × 25 and 4 × 56 Gb/s EML arrays. Both In P and thin-film lithium niobate based low half-wave voltage electro-optic modulators with modulation bandwidth over 40 GHz were demonstrated. Back-illuminated modified uni-traveling-carrier photodetectors(MUTC-PDs) with high saturation power and bandwidth exceeding 100 GHz were developed. Applications of high-speed optoelectronic devices in fiber-optic links and sub-THz wave generation are presented.

关键词： optoelectronic devices semiconductor lasers optical modulators photodetectors integrated photonic circuits

One-dimensional photonic bandgap structure in abalone shell

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2005年第14期50卷 1529-1531页

作者： LI Bo ZHOU Ji LI Longtu LI Qi HAN Shuo hao zhibiao Department of Materials Science and Engineering State Key Laboratory of New Ceramics and Fine Processing.Tsinghua University.BciJing 100084 China. Department of Materials Science and Engineering Umiversity of lllinois at Urbana-Champatgn.Urbana1L 61801.USA Department of Electronic Engineering.State Key Laboratory of Integrated Optoelectronics Tsinghull UniversityBeiJing 100084China

Photonic bandgap (PBG) materials are periodic com- posites of dielectric materials in which electromagnetic waves of certain frequency range cannot propagate in any or a special direction. Recently, there has been great inter- est in synthetic PBG materials due to their ability in ma- nipulation of photons. Since 500 million years ago, the natural world has been exploiting photonic structures for specific biological purposes[1]. Different types of biologi- cal PBG materials have been discovered in recent years, such as the one-dimension PBG structure in the sea mouse Aphrodita[2], and the fruits Elaeocarpus[3,4]; two-dimension PBG structure in the male peacock Pavo muticus feathers[5], Indonesian male Papilio palinurus butterfly[6], Thaumantis diores butterfly[7] and the male Ancyluris meliboeus Fabricius butterflies[8]; and three-dimension PBG structure in the weevil Pachyrhynchus argus[9].

关键词：光子能隙带电介质电磁波频率周期

Nonselective etching of GaN/AlGaN heterostructures by Cl2/Ar/BCl3 inductively coupled plasmas

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(Technological Sciences) 2004年第2期47卷 150-158页

作者： HAN Yanjun XUE Song WU Tong WU Zhen GUO Wenping LUO Yi hao zhibiao SUN Changzheng State Key Lab of Integrated Optoelectronics Department of Electronic Engineering Tsinghua University Beijing 100084 China

A systematic study of the nonselective and smooth etching of GaN/AIGaN het-erostructures was performed using C12/Ar/BCI3 inductively coupled plasmas (ICR).Nonselective etching can be realized by adjusting the BCI3 ratio in the Cl2/Ar/BCI3 mixture (20%—60%), increasing the ICR power and dc bias, and decreasing the chamber pressure. Surface morphology of the etched heterostructures strongly depends on the gas chemistry and the chamber pressure. Specifically, with the addition of 20% BCI3 to Cl2/Ar (4:1) gas mixture, nonselective etching of GaN/Al0.28Ga0.72N heterostructures at high etch rate is maintained and the surface root-mean-square (rms) roughness is reduced from 10.622 to 0.495 nm, which is smoother than the as-grown sample. Auger electron spectroscopy (AES) analysis shows that the effective removal of residual oxygen from the surface of AIGaN during the etching process is crucial to the nonselective and smooth etching of GaN/AIGaN herterostructures at high etch rate.

关键词： GaN Al0.28Ga0.72N ICP Cl2/Ar/BCl3 nonselective etching

Recent progresses on InGaN quantum dot light-emitting diodes

在线全文

学校读者我要写书评

暂无评论

Frontiers of Optoelectronics 2014年第3期7卷 293-299页

作者： Lai WANG Wenbin LV zhibiao hao Yi LUO Tsinghua National Laboratory for Information Science and Technology Department of Electronic Engineering Tsinghua University Beijing 100084 China

InGaN quantum dots （QDs） have attracted many research interests in recent years for their potentials to realize long wavelength visible emission from green to red, which can pave a way to fabricate the phosphor-free white light emitting diodes （LEDs）. In this paper, we reported our recent progresses on InGaN QD LEDs, the discussions were dedicated to the basic physics model of the strain relaxation in self-assembled InGaN QDs, the growth of InGaN QDs with a growth interruption method by metal organic vapor phase epitaxy, the optimization of GaN barrier growth in multilayer InGaN QDs, the demonstration of green, yellow-green and red InGaN QD LEDs, and future challenges.

关键词： quantum dot (QD) InGaN light emitting diode (LED) quantum confined Stark effect (QCSE)

基于DBR增强的850 nm GaAs/AlGaAs单行载流子光电探测器

在线全文

学校读者我要写书评

暂无评论

半导体光电 2024年第1期45卷 25-28页

作者：王健窦志鹏李光昊黄晓峰于千郝智彪熊兵孙长征韩彦军汪莱李洪涛甘霖罗毅清华大学北京国家信息科学与技术研究中心北京100084 重庆光电技术研究所重庆400060

高速850 nm GaAs/AlGaAs面入射型单行载流子光电探测器(PD)是短距离光链路中的重要器件,面临着带宽和响应度之间的相互矛盾。报道了一种基于分布布拉格反射器(DBR)增强的GaAs/AlGaAs单行载流子光电探测器(UTC-PD)。DBR由20个周期的高/... 详细信息

高速850 nm GaAs/AlGaAs面入射型单行载流子光电探测器(PD)是短距离光链路中的重要器件,面临着带宽和响应度之间的相互矛盾。报道了一种基于分布布拉格反射器(DBR)增强的GaAs/AlGaAs单行载流子光电探测器(UTC-PD)。DBR由20个周期的高/低Al组分的Al_(x)Ga_(1-x)As三元合金组成,可以在830~870 nm范围内形成大于0.9的反射。在AlGaAs DBR的增强下,将GaAs吸收层所需的厚度降低到1 040 nm,兼顾PD对光的吸收率和光生载流子的渡越时间。采用双台面、聚合物平面化、共面波导电极结构制作了UTC-PD器件。该器件在850 nm波长、-2 V偏压下具有19.26 GHz的-3 dB带宽和0.492 6 A/W的响应度。

关键词： GaAs AlGaAs 光电探测器单行载流子分布布拉格反射器 850 nm波长

Simple dynamic energy core equivalent rays method to design freeform surface for extended source

在线全文

学校读者我要写书评

暂无评论

Frontiers of Optoelectronics 2016年第2期9卷 330-337页

作者： Kun WANG Yanjun HAN Hongtao LI Yi LUO zhibiao hao Lai WANG Changzheng SUN Bing XIONG Jian WANG Tsinghua National Lab on Information Science and Technology Department of Electronic Engineering Tsinghua University Beijing 100084 China

A simple method is proposed to design free- form surface for Lambertian extended source. In this method, it can take advantage of the designing method for point source via substituting each incident ray with a dynamically calculated equivalent ray. For each facet on the freeform surface, the equivalent ray emits from the energy weighted average-emitting-position for the corre- sponding incident beam, and redirects into the direction which is determined by a source-to-target mapping. The results of the designing examples show that the light distributions＇ uniformities can be improved by this method, e.g., even the improvement of 59% can be achieved.

关键词： nonimaging optics illumination design lightemitting diodes (LEDs)