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Investigation of True Ni^(2+)-Halide Distances in Alkali Halide Lattices

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Journal of Materials Science & Technology 1994年第2期10卷 154-156页

作者： Xuanrong MA(department of physics, Ningxia university, Yinchuan, 750021, {3.)Maolu DU(Institute of Solid State physics, Sichuan Normal university, Chengdu, 610066, {3.)(To whom correspondence should be addressed) Ningxia Univ Yinchuan China

Using the μKα model of Ni2+-6X- cluster, the true distances between impurity Ni2+ cation and halide anion in alkali halide lattices are estimated from the optical spectra data. The results suggest that the true impurity cation- ligand anion distances are close to the sum of ionic radii of the impurity cation and ligand anion but not the cation - anion distance of the perfect lattices in the case of that the ionic radius of host cation is more larger than that of impurity cation

关键词： True Cl Br Investigation of True Ni Halide Distances in Alkali Halide Lattices

Entropy product measure for multipartite pure states

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Science china(physics,Mechanics & Astronomy) 2006年第5期49卷 606-615页

作者： CAO Wancang1,2, LIU Dan2, PAN Feng3.& LONG Guilu2,4 1. department of physics, Chifeng College, Chifeng 024001, china 2. Key Laboratory for Quantum Information and Measurements, department of physics, Tsinghua university, Beijing 100084, china 3. department of physics, Liaoning Normal university, Dalian 116029, china 4. Key Laboratory for Atomic and Molecular Nano-Sciences, Tsinghua university, Beijing 100084, china correspondence {13. be addressed to Long Guilu department of physics Chifeng College Chifeng 024001 China Key Laboratory for Quantum Information Measurements Department of Physics Tsinghua University Beijing 100084 China department of physics Liaoning Normal University Dalian 116029 China Key Laboratory for Atomic Molecular Nano-Sciences Tsinghua University Beijing 100084 China

An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents. Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been compared with the result of ‘the average entropy’. The new measure can be used to calculate the degree of entanglement, and an improvement is given in the area near the zero entropy.

关键词： multipartite pure state von Neumann entropy entanglement measure

Three types of maximally entangled states for a two-particle system

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Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 36-41页

作者： RUAN Manqi, XU Gang & ZENG Jinyan department of physics, Tsinghua university, Beijing 100084, {3. department of physics, Peking university, Beijing 100871, {3. correspondence should be addressed to Zeng Jinyan (email: jyzeng@***) Received June 16, 2003 1. department of physics Tsinghua University 100084 Beijing China 2. department of physics Peking University 100871 Beijing China

For a two-particle (spin 1/2) system, three fundamental forms of complete sets of commuting observables (CSCO) composed of two-body operatorsσ 1α σ 2α are given. The corresponding simultaneous eigenstates constitute three types of maximally entangled states, one of which is the well known Bell basis. This paper discusses the possible pairs of spin observables whose simultaneous measurement outcomes are definitely correlated in probabilistic fashion.

关键词： spin entangled state, complete set of commuting observables, two-body operator.

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3.& PAN Liuzhan1, 2 1. Institute of Laser physics and Chemistry, Sichuan university, Chengdu 610064, china 2. {3. of physics, Luoyang Normal College, Luoyang 471022, china 3. State Key Laboratory of Laser Technology, Huazhong university of Science and Technology, Wuhan 43.074, china correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2003 1. Institute of Laser physics and Chemistry Sichuan University 610064 Chengdu China 2. State Key Laboratory of Laser Technology Huazhong University of Science and Technology 430074 Wuhan China 3. department of physics Luoyang Normal College 471022 Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

Giant magneto-impedance and low-frequency magneto-resistance effect in NiFeB coated composite wires

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Chinese Science Bulletin 2004年第10期49卷 1002-1005页

作者： YUAN Wangzhi WANG Xinzheng ZHAO Zhenjie RUAN Jianzhong LI Xiaodong YANG Xielong department of physics, East {3. Normal university, Shanghai 200062,{3. correspondence should be addressed to Zhao Zhenjie department of physics East China Normal University Shanghai 200062 China

Composite wires of 100 μm insulated CuBewire plated with a layer of NiFeB were produced by elec-troless-deposition, and their magnetic properties were stud-led. The results showed that a good magneto-impedance (MI)effect can be obtained at relatively low frequency. The largestMI ratio (△Z/Z)max obtained is 250% at 500 kHz. Mag-neto-resistance effect was also observed at low frequency,with the (△R/R)max observed to be -8.5% at 540 Hz and 3..7% at 10 kHz. Results are discussed, and the equivalent resistance and inductance as the result of the NiFeB layer are taken into account.

关键词：巨磁阻抗无电沉积涡流电流损耗合成导线低频电机电阻

Time-division phase modulated single-photon interference in a Sagnac interferometer

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Chinese Science Bulletin 2003年第16期48卷 1704-1708页

作者： WU Guang, ZHOU Chunyuan & ZENG Heping Key Laboratory of Optical and Magnetic Resonance Spectroscopy and department of physics, East china Normal {3., Shanghai 200062, china correspondence should be addressed to Zeng Heping (e-mail: hpzeng @***) Key Laboratory of Optical and Magnetic Resonance Spectroscopy and department of physics East China Normal University Shanghai 200062 China

We introduce a stable, long-distance single- photon Sagnac interferometer, which has a balanced con-figuration to efficiently compensate phase drift caused by change of the fiber-optic path. By using time-division phase modulation, single-photon interference was realized at 1550 nm in a 5-km-long as well as 27-km-long Sagnac fiber loops, with a fringe visibility higher than 90% and long-term sta-bility. The stable performance of the single-photon interfer-ence indicated that the time-division phase-modulated Sag- nac interferometer might readily lead to practical applica-tions in single-photon routing and quantum cryptography.

关键词：单光子干涉干涉仪基本结构相位补偿时分相位调制稳定性量子密码

Piezoresistive effect in carbonnanotube films

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Chinese Science Bulletin 2003年第2期48卷 125-127页

作者： LI Yong, WANG Wanlu, LIAO Kejun, HU Chenguo, HUANG Zhi & FENG Qing department of Applied physics, Chongqing university, Chongqing 400044, {3. correspondence should be addressed to Wang Wanlu (e-mail: wanluw@ ***) department of Applied physics Chongqing University Chongqing China

The piezoresistive effect of the pristine carbon nanotube (CNT) films has been studied. Carbon nanotubes were synthesized by hot filament chemical vapor deposition. The piezoresistive effect in the pristine CNT films was stud-ied by a three-point bending test. The gauge factor for the pristine CNT films under 500 microstrains was found to be at least 65 at room temperature, and increased with tem-perature, exceeding that of polycrystalline silicon (3.) at 3.℃. The origin of the piezoresistivity in CNT films may be ascribed to a pressure-induced change in the band gap and the defects.

关键词：碳纲米管薄膜压阻效应应变系数传感器

A numerical investigation of the evolution of 2-D disturbances in hypersonic boundary layers and the effect on the flow structure due to the existence of shocklets

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 244-255页

作者： CAO Wei & ZHOU Heng department of Mechanics,Tianjin university Liu Hui Center of Applied Mathematics,Nankai and Tianjin university,Tianjin 3.0072,{3. correspondence should be addressed to Zhou Heng(email:hzhou 1 @ ***) 1. department of Mechanics Tianjin University China 2. Liu Hui Center of Applied Mathematics Nankai China 3. Tianjin university 300072 Tianjin China

The evolution of 2-D disturbances in hypersonic boundary layer with Mach number 6,8, and 10 was investigated numerically by three different numerical schemes. At the entrance, second mode T-S waves with different amplitudes were introduced, and the relation between the Mach number and the amplitude of the disturbance when shocklets started to appear was investigated. By comparing the disturbance velocity profiles with those provided by linear stability theory, the effects of shocklets on flow structures were also investigated.

关键词： hypersonic boundary layers, T-S wave, shocklet, direct numerical simulation.

Reflection of plane electromagnetic waves from the surface of a perfect conductor moving in an arbitrary direction

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Chinese Science Bulletin 2000年第17期45卷 1564-1569页

作者： HE Qicai & HUANG Yaoxiong1. department of physics, Sun Yat-sen university of Medical Sciences, Guangzhou 510089, {3. 2. Institute of Biomedical Engineering, Ji’nan university, Guangzhou 51063., {3. correspondence should be addressed to Huang Yaoxiong department of physics Sun Yat-sen University of Medical Sciences Guangzhou China Institute of Biomedical Engineering Ji’nan University Guangzhou China

The reflection of plane electromagnetic waves (TE wave and TM wave) from a perfect conductor which moves in an arbitrary direction is investigated. Based on Maxwell’s equations and the boundary conditions for moving boundary, the relation between the field vectors of reflected and incident waves, and the reflection coefficient are derived. The energy balance between incident and reflected waves, the force exerted by electromagnetic waves to the moving conductor are also discussed and some new conclusions are suggested for notice.

关键词： plane electromagnetic wave moving conductor reflection coefficient radiation pressure.