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Research progress in the inner surface modification of metal tubes by plasma processing

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Progress in Natural Science:Materials International 2006年第11期16卷 1119-1126页

作者： ZHANG Guling~ 1,2 **, WU Xingfang~1, GU Weichao~2, CHEN Guangliang~2, FENG Wenran~2, NIU Erwu~2, LI Li~2, L Guohua~2, CHEN Huan~2, FAN Songhua~2, LIU Chizi~2 and YANG Size~2(1. School of Material Science and Engineering, University of Science and Technology beijing, beijing 100083, china 2. beijing national laboratory for condensed matter physics, institute of physics, chinese academy of sciences, beijing 100080, china) School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China beijing national laboratory for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The recent progress in inner surface hardening of tubes by plasma processing is summerized. Several techniques of inner surface plasma source ion implantation and deposition are introduced, and their advantages and disadvantages are discussed. The basic principles, technical features and new progress of inner surface plasma source ion implantation methods for metal tubes, which were developed in our laboratory, are described in detail. And perspectives of the future technical development for inner surface ion implantation of tubes are presented.

关键词： PSII metal tubes inner surface surface modification.

Pairwise entanglement and local polarization of Heisenberg model

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1515-1522页

作者： XI XiaoQiang1,2, ZHANG Tao3, YUE RuiHong3,4 & LIU WuMing2 1 Department of Applied Mathematics and physics, Xi’an institute of Post and Telecommunications, Xi’an 710061, china 2.beijing national laboratory for condensed matter physics, institute of physics, chinese academy of sciences, beijing 100080, china 3 institute of Modern physics, Northwest University, Xi’an 710069, china 4 Department of physics, Ningbo University, Ningbo 315211, china Department of Applied Mathematics and physics Xi’an Institute of Post and Telecommunications Xi’an 710061 China beijing national laboratory for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China institute of Modern physics Northwest University Xi’an 710069 China Department of physics Ningbo University Ningbo 315211 China

The characteristics of pairwise entanglement and local polarization (LP) are dis-cussed by studying the ground state (states) of the Heisenberg XX model. The re-sults show that: the ground state (states) is (are) composed of the micro states with the minimal polarization (0 for even qubit and 1/2 for odd qubit); LP and the prob-ability of the micro state have an intimate relation, i.e. the stronger the LP, the smaller the probability, and the same LP corresponds to the same probability; the pairwise entanglement of the ground state is the biggest in all eigenvectors. It is found that the pairwise entanglement is decreased by the state degeneracy and the system size. The concurrence approaches a fixed value of about 0.3412.(for odd-qubit chain) or 0.3491 (for even-qubit chain) if the qubit number is large enough.

关键词： Heisenberg XX model local polarization pairwise entanglement

Oxygen vacancy induced magnetism in BaTiO_(3-δ) and Nb:BaTiO_(3-δ) thin films

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Science china(physics,Mechanics & Astronomy) 2010年第5期53卷 852-855页

作者： YANG Fang,JIN KuiJuan,LU HuiBin,HE Meng,WANG Cong,WEN Juan & YANG GuoZhen beijing national laboratory for condensed matter physics,institute of physics,chinese academy of sciences,beijing 100190,china 1. beijing national laboratory for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

The unusual magnetic properties are observed in oxygen deficient BaTiO3-δ(BTO) and Nb:BaTiO3-δ(BNTO) thin films fabricated on SrTiO3 substrates by laser molecular beam *** distinct magnetic hysteresis loops are observed in the oxygen deficient BTO and BNTO thin films in a temperature range of 5 to 300 K,whereas the diamagnetism is observed in both BTO and BNTO annealed at 1 atm of *** dopant Nb only enhances the magnetization in BNTO thin films,but has little effect on the *** magnetism of BTO and BNTO films is proposed to be the oxygen vacancies by origin.

关键词： oxygen vacancy magnetism BaTiO3-δ(BTO) Nb:BaTiO3-δ(BNTO) thin films

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) bulk metallic glass up to 24 GPa

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Science china(physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2 , ZHAN Zaiji 2 , LIU Jing 3 , YUN Jinku 1 , SUN Liling 2 , LIU Riping 1 , ZHANG Jun 2 & WANG Wenkui 1, 2 1. Key laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, china 2. Center for condensed matter physics, institute of physics, chinese academy of sciences, beijing 100080, china 3. BSRF, institute of High Energy physics, chinese academy of sciences, beijing 100039, china 1. Key laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for condensed matter physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) is investigated at room temperature up to 24 GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Negative refraction in two-dimensional photonic crystals

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Progress in Natural Science:Materials International 2006年第10期16卷 1027-1032页

作者： REN Xiaobin, REN Kun, FENG Zhifang, FENG Shuai and REN Cheng ( School of physics Science and Information Technology, Liaocheng University, Liaocheng 252059, china beijing national laboratory for condensed matter physics, institute of physics, chinese academy of sciences, beijing 100080, china) [a]School of physics Science and Information Techonolgy Liaocheng University Liaocheng China [b]beijing national laboratory for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing China

Recent progress made in research on negative refraction in two-dimensional photonic crystals is reviewed. Special attentions are paid to the research results of our group. We explore the underlying mechanism governing the occurrence of negative refraction in periodic and quasiperiodic photonic crystals. These results may be useful references for the application of photonic crystals. The perspectives of future research on negative refraction are briefly predicted.

关键词： negative refraction photonic crystals superlens subwavelength imaging equifreqnency surface.

The size effect on transport properties of colossal magnetoresistance materials La_(0.67)Ca_(0.33)MnO_3

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Science china(physics,Mechanics & Astronomy) 2008年第3期51卷 251-257页

作者： LI PeiGang1,2,LEI Ming1,2,GUO YanFeng2,GUO Xi2,CHEN LeiMing2, TANG WeiHua1,2,SONG PengYun3 & CHEN JinPing3 1 Department of physics,Center for Optoelectronics Materials and Devices,Zhejiang Sci-Tech University,Hangzhou 310018,china 2 national laboratory for condensed matter physics,institute of physics,chinese academy of sciences,beijing 100080,china 3 Department of physics,Peking University,beijing 100875,china 1. Department of physics Center for Optoelectronics Materials and Devices Zhejiang Sci-Tech University Hangzhou 310018 China 2. national laboratory for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 3. Department of physics Peking University Beijing 100875 China

High quality La0.67Ca0.33MnO3 (LCMO) film was deposited via a novel pulsed electron deposition technique on SrTiO3(100) single crystal substrate. The micro-bridge with different widths was fabricated by using electron beam lithography (EBL) technique and their transport properties were studied. For the micro-bridges with width of 2 and 1.5 μm,the insulator-to-metal transition temperature (TP) keeps un-changed compared with the film. For the micro-bridges with width of 1 μm,the TP shifts towards the lower temperature by 50 K. When the width decreases down to 500 nm,the insulator-to-metal transition disappears. The magnetoresistance be-havior of these micro-bridges was studied,and the results show that the low field magnetoresistance (LFMR) decreases and the high field magnetoresistances (HFMR) keep almost unchanged as the width of micro-bridge is reduced.

关键词： colossal magnetoresistance pulsed electron deposition electron beam lithography electrical transport properties

Fabrication of MgB2 superconducting films by different methods

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Progress in Natural Science:Materials International 2006年第2期16卷 175-177页

作者： WANG Shufang, ZHOU Yueliang, ZHU Yabin, CHEN Zhenghao, LU Huibin and YANG Guozhen ( physics & Technology College, Hebei University, Baoding 071002, china beijing national laboratory for condensed matter physics, institute of physics, chinese academy of sciences, beijing 100080, china) [a]physics & Technology College Hebei University Baoding China [b]beijing national laboratory for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing China

MgB2 superconducting films have been successfully fabricated on single crystal MgO(111) and c-AL2O3 substrates by different methods. The film deposited by pulsed laser deposition is c-axis oriented with zero resistance transition temperature of 38.4 K, while the other two films fabricated by chemical vapor deposition and electrophoresis are c-axis textured with the zero resistance transition temperature of 38 K and 39 K, respectively. Magnetization hysteresis measurements yield critical current density Jc of 107 A/cm2 at 15 K in zero field for the thin film and of 105 A/cm2 for the thick film. For the thin film deposited by chemical vapor deposition, the microwave surface resistance at 10 K is found to be as low as 100μΩ, which is comparable with that of a high-quality high-temperature superconducting thin film of YBCO.

关键词： MgB2 superconducting films chemical vapor deposition pulsed laser deposition electrophoresis.

Improvement of refrigerant capacity of La_(0.67)Ca_(0.33)MnO_(3) single crystal with a few percent Fe doping

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 809-812页

作者： LI GuoKe, ZHANG XiangQun, KOU ZhiQi, LI QingAn, SUN Young & CHENG ZhaoHua State Key laboratory of Magnetism, beijing national laboratory of condensed matter physics and institute of physics, chinese academy of sciences, beijing 100190, china State Key laboratory of Magnetism Beijing National Laboratory of Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing 100190 China

Large low-field-induced magnetic entropy changes, ΔSM, are observed in La0.67Ca0.33MnO3 and La0.67-Ca0.33Mn0.96Fe0.04O3 single crystals. The peaks of ΔSM broadened asymmetrically to high temperatures under higher magnetic fields for two materials should be attributed to the first-order magnetic phase transition at Tc. A small amount of iron doping results in an increase in the refrigerant capacity of the material though the magnetic entropy change decreases. The discovery of excellent magnetocaloric features of these single crystals in the low magnetic field can provide some ideas for exploring novel magnetic refrigerants operating under permanent magnet rather than superconducting one as magnetic field source.

关键词： single crystal magnetic entropy refrigerant capacity

New quantum tunneling steps in Mn_(11)Cr/Mn_(12. mixed crystal

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1769-1771页

作者： ZHOU YuRong1,LI YanRong1,FAN ZhenJun2 & WANG YunPing1 1beijing national laboratory for condensed matter physics,institute of physics,chinese academy of sciences,beijing 100190,china 2School of Materials sciences and Technology,china University of Geosciences,beijing 430074,china 1. beijing national laboratory for condensed matter physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China2. School of Materials Sciences and Technology China University of Geosciences Beijing 430074 China

Magnetic properties of Mn11Cr and Mn12.mixed crystal at low temperature are studied.A new set of quantum tunneling steps discovered in magnetization curves suggests that there may exist another kind of single molecula... 详细信息

关键词： quantum tunneling molecular magnet magnetization curve