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Journal of Materials Science & Technology 1998年第2期14卷 161-166页

作者： Bin WU Changyong CHEN and Shibin ZHANG(physics Dept., Lanzhou University, Lanzhou 730000, china)Wanlu WANG and Kejun LIAO(Applied physics Dept., Chongqing University, Chongqing 400044, china) physics Dept. Lanzhou University Lanzhou 730000 China Applied physics Dept. Chongqing University Chongqing 400044 China

Transparent conductive cadmium indium oxide films (CdIn2O4) were prepared by r.f. reactive sputtering from Cd-In alloy targets under an Ar-O2 atmosphere. Electrical conductivity of the order of 105Ω-1.m-1 and the optical transmission as high as 94% are easily attained by postdeposition annealing treatment. The effects of oxygen concentration in the reactive gas mixture and post-deposition annealing treatment on the optical transmittance as well as optical parameters, such as refractive index (n), extinction coefficient (k), real part (ε') and imaginary part (ε') of the dielectric constant, were studied in the visible and near-infrared region. The highfrequency dielectric constant ε∞ the plasma frequency ωP, and the conduction band effective mass mc of different samples were also investigated

关键词： Thin Effect of Oxygen Concentration and Annealing Theatment on the Optical Properties of the Transparent Conductive CdIn2O4 Thin Films

Electronic structure and magnetism of Fe-doped SiC nanotubes

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2,3,ZHANG FuChun3,ZHANG ZhiYong4,LU ShuYuan5 & YANG YanNing3 1 Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710068,china 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 3 College of physics and Electronic Information,Yan’an University,Yan’an 716000,china 4 Information Science and Technology Institution,Northwest University,Xi’an 71012.,china 5 Department of Telecommunications,Xi’an Institute of Posts and Telecommunications,Xi’an 71012.,china 1. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710068 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. College of Physics and Electronic Information Yan’an University Yan’an 716000 China4. Information Science and Technology Institution Northwest University Xi’an 710127 China5. Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an 710121 China

The electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).The calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is 3.2 eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si 3p electron spins and Fe 3d electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired 3d electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties

X-ray flares of γ-ray bursts: Quakes of solid quark stars?

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Science china(physics,Mechanics & Astronomy) 2009年第2期52卷 315-320页

作者： XU RenXin1 & LIANG EnWei2 1 School of physics and State Key Laboratory of Nuclear physics and Technology, Peking University, Beijing 100871, china 2 Department of physics, Guangxi University, Nanning 530004, china 1. School of physics and State Key Laboratory of Nuclear physics and Technology Peking University Beijing 100871 China 2. Department of physics Guangxi University Nanning 530004 China

A star-quake model is proposed to understand X-ray flares of both long and short γ-ray bursts (GRBs) in a solid quark star regime. Two kinds of central engines for GRBs are available if pulsar-like stars are actually (solid) quark stars, i.e., the SNE-type GRBs and the SGR-type GRBs. It is found that a quark star could be solidified about 103 to 106 s later after its birth if the critical temperature of phase transi- tion is a few Metga-electron-volts, and then a new source of free energy (i.e., elastic and gravitational ones, rather than rotational or magnetic energy) could be possible to power GRB X-ray flares.

关键词： γ-rays bursts: X-rays neutron stars elementary particles

Selected issues at the interface between nuclear physics and astrophysics as well as the standard model

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 119-123页

作者： MENG Jie1,2,3, NIU ZhongMing1, LIANG HaoZhao1 & SUN BaoHua2,4 1State Key Laboratory of Nuclear physics and Technology, School of physics, Peking University, Beijing 100871, china 2School of physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, china 3Department of physics, University of Stellenbosch, Stellenbosch, South Africa 4Justus-Liebig-Universita¨t Giessen, Heinrich-Buff-Ring 14, Giessen 35392, Germany 1. State Key Laboratory of Nuclear physics and Technology School of Physics Peking University Beijing 100871 China 2. School of physics and Nuclear Energy Engineering Beihang University Beijing 100191 China 3. Department of physics University of Stellenbosch Stellenbosch South Africa 4. Justus-Liebig-Universit?t Giessen Heinrich-Buff-Ring 14 Giessen 35392 Germany

The density functional theory (DFT) with a minimal number of parameters allows a very successful phenomenological description of ground state properties of nuclei all over the periodic table. The recent developments on the application of the covariant density functional theory as well as its extensions by the group in Beijing for a series of interests and hot topics in nuclear astrophysics and nuclear structure are reviewed, including the rapid neutron-capture process, Th/U chronometer, and isospin corrections for superallowed β transitions.

关键词： rapid neutron-capture process nuclear chronometer isospin symmetry-breaking corrections

The Research of Scattering Cross-Section and Energy-Extraction in FEL

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Chinese Journal of Lasers 1995年第1期B4卷 25-29页

作者： ZHU Jiaqing (Department of physics,Central china Normal University,Wuhan,430070,china) Central china Normal Univ Wuhan China

ＴｈｅＲｅｓｅａｒｃｈｏｆＳｃａｔｔｅｒｉｎｇＣｒｏｓｓ－ＳｅｃｔｉｏｎａｎｄＥｎｅｒｇｙ－ＥｘｔｒａｃｔｉｏｎｉｎＦＥＬＴｈｅＲｅｓｅａｒｃｈｏｆＳｃａｔｔｅｒｉｎｇＣｒｏｓｓ－ＳｅｃｔｉｏｎａｎｄＥｎｅｒｇｙ－Ｅ... 详细信息

ＴｈｅＲｅｓｅａｒｃｈｏｆＳｃａｔｔｅｒｉｎｇＣｒｏｓｓ－ＳｅｃｔｉｏｎａｎｄＥｎｅｒｇｙ－ＥｘｔｒａｃｔｉｏｎｉｎＦＥＬＴｈｅＲｅｓｅａｒｃｈｏｆＳｃａｔｔｅｒｉｎｇＣｒｏｓｓ－ＳｅｃｔｉｏｎａｎｄＥｎｅｒｇｙ－ＥｘｔｒａｃｔｉｏｎｉｎＦＥＬ￥ＺＨ...

关键词： free-electron laser scattering cross-section

Studies of low-lying states of even-even Xe isotopes within the nucleon pair approximation

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 103-108页

作者： ZHANG LiHua1, JIANG Hui1,2 & ZHAO YuMin1,3,4 1Institute of Nuclear, Particle, Astrophysics and Cosmology, Department of physics, Shanghai Jiao Tong University, Shanghai 200240, china 2School of Arts and Sciences, Shanghai Maritime University, Shanghai 200135, china 3Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, china 4CCAST, World Laboratory, P.O. Box 8730, Beijing 100080, china 1. Institute of Nuclear Particle Astrophysics and Cosmology Department of Physics Shanghai Jiao Tong University Shanghai 200240 China2. School of Arts and Sciences Shanghai Maritime University Shanghai 200135 China3. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China4. CCAST World Laboratory P.O. Box 8730 Beijing 100080 China

We study the relevance of nucleon pairs with higher spins, in addition to spin-zero and spin-two pairs (i.e., S D pairs), in low-lying states of even-even Xe nuclei. By including those higher-spin pairs in our configuration, we recalculate energy level schemes, elec trical quadrupole moments, magnetic moments and electric quadrupole transition rates, for low-lying states of even-even 12.-142Xe nuclei. The agreement between our calculated results and the experimental data is substantially improved in comparison with previous studies.

关键词： nucleon pair approximation shell model configuration space low-lying states

A general information theoretical proof for the second law of thermodynamics

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Science china(physics,Mechanics & Astronomy) 2008年第7期51卷 813-816页

作者： ZHANG QiRen Department of Technical physics, Peking University, Beijing 100871, china 1. Department of Technical physics Peking University Beijing 100871 China

It is shown that the conservation and the non-additivity of the information, together with the additivity of the entropy, make the entropy increase in an isolated system. The collapse of the entangled quantum state offers an example of the information non-additivity. Nevertheless, the non-additivity of information is also true in other fields in which the interaction information is important. Examples are classical statistical mechanics, social statistics and financial processes. The second law of thermodynamics is thus proven in its most general form. It is exactly true not only in quantum and classical physics but also in other processes in which the information is conservative and non-additive.

关键词： information conservation non-additivity of information entropy increase

Spatial Carrier Bi-frequency Fourier Transform Profilometry for the 3-D Shape Measurement of Object with Discontinuous Height Steps

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Chinese Journal of Lasers 2000年第2期9卷 121-127页

作者： ZHONG Jingang DI Hongwei ZHANG Yonglin (Deportment of physics, Jinan University, Guangzhou 510632, china ) 济南大学广东广州

The combination of shearing interferometer, Fourier-transform profilometry, phase unwrapping by lockup table method has resulted in a new and more powerful method of measuring surface profile. The technique permits the three-dimensional shape measurement of objects that have discontinuous height steps. Experimental results have demonstrated the validity of the principle.

关键词： profilometry bi-frequency phase unwrapping discontinuous height step

Energy Spectrum of YAG:Cr3+ and Thermal Shifts of Its R Lines

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Communications in Theoretical physics 2005年第7期44卷 165-170页

作者： MA Dong--Ping CHEN Ju--Rong Department of Applied physics, Sichuan University, Chengdu 610065, china International Centre for Materials physics, the Chinese Academy of Sciences, Shenyang 110015, china Department of Applied physics Sichuan University International Centre for Materials physics the Chinese Academy of Sciences

Traditional ligand-field theory has to be improved bv taking into account both "pure electronic" contributionand electron-phonon interaction one （including lattice-vitbrational relaxation energv）. By means of improved ligand-fieldtheory, R1, R2, R3′, R2′, and R1′ lines, U band, ground-state zero-field-splitting （GSZFS） and ground-state g factors aswell as thermal shifts of R1line and R2line of YAG:Cr3+have been calculated. The results are in very good agreementwith the experimental data. In contrast with ruby, the octahedron of ligand oxygen ions surrounding the central Cr3+ion in YAG:Cr3+is compressed along the [111] direction. Thus, for YAG:Cr3+and ruby, the splitting of t23 4A2(or t23 2E)has opposite order, and the trigonal-field parameters of the two crystals have opposite signs. In thermal shifts of R1andR2lines of YAG:Cr3+, the tetnperature-dependent contributions due to EPI are dominant.

关键词： improved ligand-field theory electron-phonon interaction Stokes shift energy spectrum thermal shift g factor

Stability of proton and maximally symmetric minimal unification model for basic forces and building blocks of matter

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Science china(physics,Mechanics & Astronomy) 2007年第3期50卷 303-310页

作者： WU YueLiang Institute of Theoretical physics, Chinese Academy of Sciences, Beijing 100080, china 1. Institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China

With the hypothesis that all independent degrees of freedom of basic building blocks should be treated equally on the same footing and correlated by a possible maximal symmetry, we arrive at a 4-dimensional space-time unification model. In this model the basic building blocks are Majorana fermions in the spinor repre- sentation of 14-dimensional quantum space-time with a gauge symmetry GM4D = SO(1,3)×SU(32)×U(1)A×SU(3)F. The model leads to new physics including mirror particles of the standard model. It enables us to issue some fundamental questions that include: why our living space-time is 4-dimensional, why parity is not con- served in our world, how the stability of proton is, what the origin of CP violation is and what the dark matter can be.

关键词： gauge symmetry space-time symmetries beyond standard model and unification