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Channel characterization at 12. GHz for future indoor communication systems

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chinese Physics B 2013年第5期22卷 650-656页

作者：陈镇曹俊诚 key laboratory of {2. Solid-state technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences

We present a simulation on the spatial and temporal characteristics of the indoor propagation channel at 12. GHz. The simulation, applied to a dynamic scenario with randomly placed objects and moving people in a room, is based on a three-dimensional ray-tracing method. Propagation and reflection mechanisms of electromagnetic waves are discussed in the channel model. The received power in a 0.95-m-height plane is obtained. Comparison between walls and ceiling covered with dielectric mirrors and those with three common wall and ceiling materials are presented. The result shows that the holistic received power level with dielectric mirrors is about 10 dB higher than with other materials.

关键词： sub-terahertz communication channel models ray tracing electromagnetic propagation

Performance analysis of LDPC codes on OOK terahertz wireless channels

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chinese Physics B 2016年第2期25卷 553-557页

作者：刘纯王长曹俊诚 key laboratory of {2. Solid-state technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Science

Atmospheric absorption, scattering, and scintillation are the major causes to deteriorate the transmission quality of terahertz（THz） wireless communications. An error control coding scheme based on low density parity check（LDPC） codes with soft decision decoding algorithm is proposed to improve the bit-error-rate（BER） performance of an on-off keying（OOK） modulated THz signal through atmospheric channel. The THz wave propagation characteristics and channel model in atmosphere is set up. Numerical simulations validate the great performance of LDPC codes against the atmospheric fading and demonstrate the huge potential in future ultra-high speed beyond Gbps THz communications.

关键词： terahertz wireless channels low density parity check codes atmospheric turbulence gamma-gamma models

Fabrication of thick BOX SOI by Smart-cut technology

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Nuclear Science and Techniques 2003年第2期14卷 115-118页

作者： WU Yan-Jun, ZHANG Miao, AN Zheng-Hua, LIN Cheng-Lu(state key {2. of Functional Materials for Informatics, shanghai institute of microsystem and information technology,the chinese academy of sciences, shanghai 2.0050) shanghai institute of microsystem and information technology the Chinese Academy of Sciences State Key Laboratory of Functional Materials for Informatics 上海 200050

A SOI material with thick BOX (2.2.μm) was successfully fabricated using the Smart-cut technology. The thick BOX SOI microstructures were investigated by high resolution cross-sectional transmission electron microscopy (XTEM), while the electrical properties were studied by the spreading resistance profile (SRP). Experimental results demonstrate that both structural and electrical properties of the SOI structure are very good.

关键词：灵活切割技术微观结构截面透射电子显微镜 XTEM 电学特性绝缘硅片 SOI

Tunneling conductance in graphene ferromagnet/p wave superconductor junctions

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Science china(Physics,Mechanics & Astronomy) 2012年第4期Mechanics & Astronomy) .卷 649-653页

作者： LI XiaoWei 1,2.,CHEN HuaBao 1 & LIU ShuJing 1 1 School of Physics and Electronic Electrical Engineering,Huaiyin Normal University,Huaian 2.3300,china 2.state {2. laboratory of Functional Materials for Informatics,shanghai institute of microsystem and information technology,chinese academy of sciences,shanghai 2.0050,china 1. School of Physics and Electronic Electrical Engineering Huaiyin Normal University Huaian 223300 China2. State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Using the extended Blonder-Tinkham-Klapwijk formalism,we investigate the conductance spectra of graphene ferromagnet/p wave superconductor *** is found that the conductance spectra are affected by the p wave pairing *** ferromagnetic exchange energy in the ferromagnet can suppress Andreev retroreflection but enhance the specular Andreev reflection in graphene ferromagnet/p wave superconductor *** conductance decreases with increasing exchange energy Eh for EhEF.

关键词： graphene ferromagnet p wave superconductor tunneling conductance

Gettering of copper impurity in silicon by aluminum precipitates and cavities

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Nuclear Science and Techniques 2003年第3期14卷 164-167页

作者： WU Yan-Jun, ZHANG Miao, ZHANG Ning-Lin, LIN Cheng-Lu(state key {2. of Functional Materials for Informatics. shanghai institute of microsystem and information technology.the chinese academy of sciences, shanghai 2.0050) shanghai institute of microsystem and information technology the Chinese Academy of Sciences State Key Laboratory of Functional Materials for Informatics 上海 200050

Al precipitates as well as cavities (or open-volume detects) are known for their ability to getter impuri-ties within Si. In order to compare their relative gettering strength we produced both Al precipitates and cavities atdifferent depths within one Si wafer. This was done by H+ and Al+ implantation with different energies and subse-quent annealing process, resulting in Al-Si alloy and cavities at depth of 300 nm and 800 nm, respectively. Cu wasthen implanted with an energy of 70 keV to a fluence of 1 × 1014 / cm2. The Cu implanted samples were annealed attemperature from 700℃ to 12.0℃. It was found that Cu impurities were gettered primarily by the precipitated Allayer rather than by cavities at the temperature of 700～1000℃, while gettering of Cu occured in both regions at thetemperature of 12.0℃. The secondary ion mass spectrometry and transmission electron microscopy analyses wereused to reveal the interaction between Cu impurities and defects at different trap sites.

关键词：铜硅片铝过渡金属元素

Two crucial factors influencing quality of GaAs on Ge substrate

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chinese Physics B 2014年第4期23卷 488-491页

作者：邓闯门传玲陈达 School of Energy and Power Engineering University of Shanghai for Science and Technology state key {2. of Functional Materials for Informatics Institute of Microsystem and Information TechnologyChinese Academy of Sciences

High-quality GaAs films with fine surfaces and GaAs/Ge interfaces on Ge have been achieved via molecular beam epitaxy. The influence of low temperature annealing and low temperature epitaxy on the quality of the film when GaAs is grown on a （100） 6 ° offcut towards [111] Ge substrate are investigated by analyzing and comparing the GaAs films that are fabricated via three different processes. A low temperature annealing process after high temperature annealing and a low temperature epitaxy process after the initial GaAs growth play a vital role in improving the quality of GaAs film on a Ge substrate.

关键词： molecular beam epitaxy low temperature annealing low temperature epitaxy

Suppressed Antiferromagnetism and Superconductivity in As-deficient Iron-based Superconductor of SrFe_(1.8)Co_(0.2.As_x

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稀有金属材料与工程 2011年第S3期40卷 358-361页

作者： Liu Zhiyong1, Lu Yuming1, Liu Jinlei1, Qu Chunqing1,2.3, Chen Changzhao1, Cai Chuanbing1, Huang Fuqiang3, Xie Xiaoming2.1 shanghai University, shanghai 2.0444, {2. 2.state key laboratory of Functional Materials for Informatics,shanghai institute of microsystem and information technology,chinese academy of sciences,shanghai 2.0050, {2. 3 shanghai institute of Ceramics, chinese academy of sciences, shanghai 2.0050, {2. shanghai Univ Res Ctr Superconductors & Appl Technol Shanghai 200444 Peoples R China chinese Acad Sci Shanghai Inst Microsyst & Informat Technol State Key Lab Funct Mat Informat Shanghai 200050 Peoples R China chinese Acad Sci Shanghai Inst Ceram Shanghai 200050 Peoples R China

Iron-based superconductors namely Sr(Fe1.8Co0.2.As1.8 (FeAs1.8) and Sr(Fe1.8Co0.2.As1.85 (FeAs1.85) with As deficiency are prepared by solid-state reaction. X-ray diffraction reveals that the polycrystalline phase forms in the studied samples, identical to typical SrFe2.s2.(12.) matrix. Resistive and magnetic measurements show that the superconducting transition temperatures (Tc) are about 19 K for both FeAs1.8 and FeAs1.85. Compared with the performances of typical iron-based 12. superconductors arising from Co doping, the present samples show the suppressed superconductivity. Moreover, the antiferromagnetic (AFM) phase correlated with spin-density-wave (SDW) is reduced as well. The AFM transition temperature decreases to 12. K for FeAs1.85, while such a phase transition is absent at all for FeAs1.8, one sample with less As, implying that the existence of SDW and antiferromagnetism is more sensitive to As content.

关键词： antiferromagnetism superconductivity iron-based superconductors

Reduction of self-heating effect in SOI MOSFET by forming a new buried layer structure

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Nuclear Science and Techniques 2003年第2期14卷 119-122页

作者： ZHU Ming, LIN Qing, LIU Xiang-Hua, LIN Zi-Xin, ZHANG Zheng-Xuan, LIN Cheng-Lu(state key {2. of Functional Materials for Informatics, Shanghal institute of microsystem and information technology,the chinese academy of sciences, shanghai 2.0050) shanghai institute of microsystem and information technology the Chinese Academy of Sciences State Key Laboratory of Functional Materials for Informatics 上海 200050

An inherent self-heating effect of the silicon-on-insulator (SOI) devices limits their application at high current levels. In this paper a novel solution to reduce the self-heating effect is proposed, based on N+ and O+ co-implantation into silicon wafer to form a new buried layer structure. This new structure was simulated using Medici program, and the temperature distribution and output characteristics were compared with those of the conventional SOI counterparts. As expected, a reduction of self-heating effect in the novel SOI device was observed.

关键词：自动加热效应埋存层状结构绝缘硅片 SOI 二氧化硅

Conjugate adjoining problem in braid groups and new design of braid-based signatures

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Science china(information {2.) 2010年第3期53卷 524-536页

作者： WANG LiCheng1,2. WANG LiHua2. cao ZhenFu3, YANG YiXian1 & NIU XinXin1 information Security Center, {2. key laboratory of Networking and Switching technology, Beijing University of Posts and Telecommunications, Beijing 100876, china 2.ational institute of information and Communications technology, Tokyo 184-8795, Japan 3Trusted Digital technology laboratory, {12. Jiao Tong University, {12. 2.02.0, china 1. information Security Center State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China2. National Institute of Information and Communications Technology Tokyo 184-8795 Japan3. Trusted Digital Technology Laboratory Shanghai Jiao Tong University Shanghai 200240 China

The development of quantum computation casts serious threats to the securities of most existing public-key cryptosystems. Braid-based cryptography is one of the alternatives that have potential advantages in resisting quantum attacks. In this paper, the state of the art of braid cryptography is surveyed, and then a new cryptographic problem-conjugate adjoining problem related to braid groups is proposed. Based on this problem, we design a new braid-based signature scheme. This scheme is efficient and provably secure in the random oracle model. Further, we present the comparison between braid-based signatures and RSA-based ones. The signing process of the braid-based schemes is more efficient than that of RSA-based ones, while the verifying process of the braid-based ones is observably slow. Hence, braid-based signatures are suitable for scenarios where the signing process has to be as quick as possible but delays are permitted in the verifying process, for example, in off-line e-cash systems. The key sizes in braid-based schemes are considerably large-about 2. bits in the case of secret keys and 12. bits in the case of public keys. However, braid operations are much simpler and more efficient than modular exponential operations. Therefore, braid-based schemes can be embedded into devices with low computational ability and large memory space. The capability of braid cryptosystems to resist currently known quantum attacks is also discussed from the perspective of hidden subgroup problems.

关键词： braid group conjugate adjoining problem digital signature provable security resistance to quantum attack