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Correspondence Between Oscillations and Emitted Photon Closed-Orbits in Spontaneous Emission Rate of an Atom Near a Dielectric Slab

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Communications in Theoretical Physics 2007年第5期47卷 887-891页

作者： yun Su-Jun WANG Fu-He zhou yun-song DU Meng-Li Departrnent of Physics Capital Normal University. Beijing 100037 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China

We study the oscillations in the spontaneous emission rate of an atom near a dielectric slab. The emission rate is calculated as a function of system size using quantum electrodynamics. It exhibits multi-periodic oscillations. Four frequencies of the oscillations are extracted by Fourier transforms. They agree with actions of photon closed-orbits going away and returning to the atom. These oscillations are explained as manifestations of quantum interference effects between the emitted photon wave near the atom and the returning photon waves travelling along various closed-orbits.

关键词： quantum electrodynamics photon closed-orbit spontaneous emission Fourier transform

Critical Point of Ising Films with Different Growth Directions

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Chinese Physics Letters 2000年第1期17卷 55-57页

作者： WANG Huai-yu zhou yun-song D.L.Lin Department of Physics Yantai UniversityYantai 264005 Department of Physics Capital Normal UniversityBeijing 100037 Department of Physics State University of New York at BuffaloBuffaloNY 14260-1500U.S.A.

The critical temperature Tc of a spin-1/2 Ising film of cubic structures is calculated by the variational cumulant expansion method for three directions of *** results from different growth directions are analysed and compared with each *** the present model,the Tc values depend largely on the number of nearest neighbors in a monolayer for films with the same number of monolayers but grown in different *** sc,bcc and fee structures,the highest Tc is found along the(100),(110),and(111)direction,respectively.

关键词： directions Ising variational

Identification and primary genetic analysis of Arabidopsis stomatal mutants in response to multiple stresses

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Chinese Science Bulletin 2006年第21期51卷 2586-2594页

作者： song Yuwei KANG Yanli LIU Hao ZHAO Xiaoliang WANG Pengtao AN Guoyong zhou yun MIAO Chen song Chunpeng Laboratory of Plant Stress Biology Department of Biology Henan University Kaifeng 475001 China

In response to variable environmental conditions, guard cells located in the leaf epidermis can integrate and cope with a multitude of complicated stimuli, thereby making stomata in an appro- priate state. However, many signaling components in guard cell signaling remain elusive. In our laboratory, a tool for non-invasive remote infrared thermal images was used to screen an ethyl methane sulfonate-mutagenized population for Arabidopsis stomatal response mutants under multiple stresses (ABA, H2O2, CO2, etc.). More than forty "hot" or "cold" mutants were isolated (above or below 0.5℃ in con- trast to normal plantlets). Identification and primary genetic analysis of these mutants show that they are monogenic recessive mutations and there exist distinct difference in stomata apertures compared to wild type. These mutants in response to various environmental stresses and hormones were comprehen- sively investigated, which enables us to further un- derstand the cross-talk in different signal transduction pathways.

关键词：红外摄象机保卫细胞遗传分析信号转导变异

Interface Effects on the Magneto-Optical Kerr Effect and Optical Properties in Co/Ni Multilayer

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Chinese Physics Letters 2001年第8期18卷 1117-1119页

作者： WANG Hai zhou yun-song CHEN Jin-Chang LI Tong ZHAO Hong-Wu ZHAN Wen-Shan WANG song-You CHEN Liang-Yao State Key Laboratory for Magnetism Institute of Physics and Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080 Department of Physics Capital Normal UniversityBeijing 100037 Department of Physics and Material Science Fudan UniversityShanghai 200433

The influence of interfaces on the magneto-optical Kerr effect in the Co/Ni multilayer has been *** was found that the magnetic-optical Kerr rotation varies with the numbers of interfaces(x)in Co/Ni multilayer,which indicated that the interface states play an important role in the Kerr ***,ellipticity and optical constants n and k are also found to vary with *** possible mechanisms have been discussed.

关键词： effect. multilayer rotation

Numerical Confirmation of Multi-Reflections of Light Inside a Subwavelength Metal Slit Structure

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Chinese Physics Letters 2010年第3期27卷 282-285页

作者：周云松顾本源王怀玉兰胜 Department of Physics Capital Normal University Beijing 100048 Institute of Physics Chinese Academy oF Sciences PO Box 603 Beijing 100190 Department of Physics Tsinghua University Beijing 100084 Laboratory of Photonic Information Technology School for Information and Optoelectronic Science and Engineering South China Normal University Guangzhou 510006

The propagation behavior of light passing through a subwavelength metal slit structure is usually modeled by a Fabry-Perot （FP） resonant cavity based on the feature of transmission spectra. However, this mechanism belongs to a conjecture and it should be proven. We present a direct evidence from the numerical simulations of the amplitude distribution of the magnetic field by employing the time-domain simulation method. The light propagation behavior clearly shows a multi-reflection process inside a subwavelength slit as soon as it enters the slit. An analytical formula for calculating the field distribution involving the multi-reflection process is presented, and the theoretical calculations agree with the numerically simulated results. Our results provide explicit evidence that the FP model is reasonable to the description of the propagation process of light inside a subwavelength slit structure.

关键词： Surfaces interfaces and thin films

基于分数阶傅里叶变换的宽带LFM信号波达方向估计新算法

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北京理工大学学报 2005年第10期25卷 895-899页

作者：陶然周云松北京理工大学信息科学技术学院电子工程系北京100081

提出一种新的基于分数阶傅里叶变换和信号子空间分解的宽带线性调频(LFM)信号波达方向(DOA)估计算法.该方法利用LFM信号在分数阶傅里叶变换域的极高的聚集性,在分数阶傅里叶变换域分离信号,并构造分数阶傅里叶变换域的阵列信号相关矩阵... 详细信息

提出一种新的基于分数阶傅里叶变换和信号子空间分解的宽带线性调频(LFM)信号波达方向(DOA)估计算法.该方法利用LFM信号在分数阶傅里叶变换域的极高的聚集性,在分数阶傅里叶变换域分离信号,并构造分数阶傅里叶变换域的阵列信号相关矩阵.通过对相关矩阵进行特征值分解,估计信号子空间和噪声子空间,并利用MU S IC算法估计宽带LFM信号的波达方向.仿真验证了新方法的有效性.

关键词：分数阶傅里叶变换线性调频信号波达方向估计 MUSIC算法

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影响近场光纤探针传输效率的若干因素

光谱学与光谱分析 2011年第10期31卷 2602-2605页

作者：黄巍戴松涛王怀玉周云松清华大学物理系北京100084 首都师范大学物理系北京100048

近场光学技术在高分辨率成像、光谱探测和纳米加工等领域有广泛应用,而光纤探针是其中一个关键部件。如何提高光纤探针的传输效率是近场光学技术应用中的一个重要问题。本文采用三维时域有限差分方法,计算了锥形有孔探针的传输效率,分... 详细信息

近场光学技术在高分辨率成像、光谱探测和纳米加工等领域有广泛应用,而光纤探针是其中一个关键部件。如何提高光纤探针的传输效率是近场光学技术应用中的一个重要问题。本文采用三维时域有限差分方法,计算了锥形有孔探针的传输效率,分析了锥角、针尖孔径、波长和金属层厚度等因素对光纤探针传输效率的影响,并比较了裸光纤探针和有金属涂层的光纤探针在传输效率和空间分辨率上的差异。此外,还发现了传输效率随入射光波长变化出现的振荡现象。

关键词：近场光纤探针时域有限差分方法传输效率

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多层伊辛膜的磁学性质

物理学报 2000年第12期49卷 2477-2481页

作者：周云松陈金昌林多梁首都师范大学物理系北京100037 纽约州立布法罗大学物理系

用变分累积展开 (VCE)方法的一阶近似计算了包括最近邻和次近邻作用的多层伊辛膜的磁学性质 ,导出了自发磁化强度、矫顽力、居里点、奈尔点、顺磁磁化率及分子场系数与层数的关系表达式。

关键词：多层膜伊辛模型磁化磁学性质薄膜

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二维正方格子磁性光子晶体的带隙结构

物理学报 2005年第10期54卷 4770-4775页

作者：车明周云松王福合顾本源首都师范大学物理系北京100037 中国科学院物理研究所北京100080

采用平面波展开的方法计算了正方格子二维磁性光子晶体(MPC)的光子带隙结构.散射子的形状分别为长方形,正方形,六角形和圆形.通过调节磁导率,填充率和散射子的旋转角度,找到了MPC各种结构的最大的绝对带隙宽高比ωR.研究发现随着磁导率... 详细信息

采用平面波展开的方法计算了正方格子二维磁性光子晶体(MPC)的光子带隙结构.散射子的形状分别为长方形,正方形,六角形和圆形.通过调节磁导率,填充率和散射子的旋转角度,找到了MPC各种结构的最大的绝对带隙宽高比ωR.研究发现随着磁导率的增加,MPC绝对带隙中心频率ωg单调减小,绝对带隙宽度Δω和其宽高比ωR可能不同时达到最大值.而随着填充率或者散射子旋转角的增加,基本不改变ωg的大小,各种结构的Δω和ωR同时达到最大值.

关键词：磁性光子晶体光子带隙结构二维磁性光子晶体正方格子旋转角度平面波展开中心频率带隙宽度磁导率