bluuebunny/crossref_metadata_2025 huggingface dataset:
INTERACTION POTENTIAL FIELD BETWEEN A GEOMET-RICAL KINK AND A POINT DEFECT
Authors: SUN ZONG-QI  ,   中国科学院金属研究所,沈阳110015
Published: December 2020

A vector expression of the dilatotion field of a segment of dislocation line was obtained with isotropic elasticity. The interaction potential field between a geometric kink, made of straight segments or a smooth curve of dislocation, and a point defect was thus obtained. The distribution of the potential along the dislocation tube for different types and widths of kink was calculated numerically.The possibility of the dislocation relaxation associated with the interaction between a mobile vacancy and the geometric kink on screw and mixed dislocations was analysed.
SYMMETRY THEORY OF THE MAGNETIC PHASE TRANSITION OF FeRh ALLOY
Authors: ZHONG LI-JUN  , TAO RUI-BAO  ,   (1)复旦大学物理系,上海200433; (2)复旦大学物理系,上海200433;北京261信箱,国家玻璃钢质检中心,北京102101
Published: December 2020

The formula of the Molien function in the case of corepresentation is derived by application of the symmetry theory for second order phase transition to magnetic systems, it is different from that of unitary groups. The analysis of the magnetic phase transition of FeRh alloy shows that eqivalent representation in the sense of corepresentation may lead to different symmetry breaking for the reason of none-quivalent characters. The result that a continuous magnetic phase transition Oh1⊕θOh1→C4v1⊕θ[D4h1-C4v1] exists theoretically is supported by experiments.
GENERALIZED KUROSAWA RELATION AND LST RELATION AND THEIR EXPERIMENTAL VERIFICATION
Authors: JIANG YI-JIAN  , LIAO LI-JI  , CHEN GANG  , ZENG LING-ZHI  , JIN YING  ,   (1)北京大学物理系,北京100871; (2)北京工业大学应用物理系,北京100022
Published: December 2020

Under the condition of qc?ω, the generalized frequency dispersion relation of polar pho-nons is simplified- The generalized Kurosawa relation and LST relation are derived and verified by the Raman spectra of TGS singal crystal.
SUBSONIC AND SUPERSONIC SOLITONS IN ONE DIMENSIONAL LINEAR CHAINS
Authors: ZHOU YI-CHANG  , YU CHAO-FAN  ,   (1)广东教育学院物理系,广州510303; (2)中山大学物理系,广州510275
Published: December 2020

The interaction between electrons and acoustic lattice vibrations is investigated by the method of coherent states, giving out the solutions of solitons which can travel with subsonic or supersonic velocities. The form and energy of the solitons is given.
MICROWAVE MAGNETIC RESONANCE IN REENTRANT SPIN GLASS SPINEL CoxZn1-x(FeyCr1-y)2O4
Authors: ZHOU WEN-SHENG  , XU DONG  ,   北京大学物理系,北京100871
Published: December 2020

A microwave magnetic resonance experiment has been performed on the spinel system CoxZn1-x(FeyCr1-y)2O4 in the reentrant spin glass region (0.4≤x≤0.8, y = 0.5, 0.8). The temperatue dependence of the line shape, linewidth, resonant field, g-factor, and the relationship of the linewidth to the concentration of magnetic ions have been studied. The mechanism of the experimental phenomena has been discussed using the spin clustering effect and the local random field model. The microwave magnetic resonance properties in the system can be attributed to the formation of spin clusters, the establishment of the long-range ferrimagnetic order, the collapse of the ferrimagnetic order and random freezing of spin clusters.
INVESTIGATION ON THE PHYSICAL PROPERTIES AND DEFECTS OF Cd2SnO4 FILMS DEPOSITED BY RF REACTIVE SPUTTERING
Authors: PENG DONG-LIANG  , JIANG SHENG-RUI  ,   兰州大学物理系,兰州730000
Published: December 2020

Transparent conductiong films of cadmium-tin oxide were prepared by rf reactive sputtering from a Cd-Sn alloy target in an Ar-O2 atmosphere. The structure of the films was examined by X-ray diffraction. The electrical and optical properties of the films were found to depend on the oxygen concentration in the gas mixture and the substrate temperature as well as the post-deposition heat treatment. The lowest resistivity obtained was 1.74×10-6Ω·cm and the highest optical transmission was 95% over the visible region. For the films deposited at substrate temperature of 400℃ in an Ar-O2 atmosphere of 6% O2, heat treatment increased the optical gap energy from 2.37eV to 2.64eV.
THEORETICAL CALCULATION OF VIBRATIONAL AND ROTATIONAL TRANSITION PROBABILITIES FOR THE ATOM-OSCILLATOR SCATTERING
Authors: REN TING-QI  , WANG QI-XIN  , ZHANG QING-GANG  , ZHANG YI-CI  ,   (1)山东师范大学物理系,济南250014; (2)烟台师范学院物理系,烟台264025
Published: December 2020

In the interaction representation, the time-dependent quantum calculation formulas for the atom-oscillator scattering are derived by using angular momentum coupling theory, and the vibrational and rotational transition probabilities and the partial cross sections for the He-H2 system are calculated. The results show that: (1) the interaction picture wave function is highly localized in coordinate space and varies slowly in time, therefore, we are able to obtain higher accuracy in calculating scattering quantities, and the calculated results are in excellent agreement with that of CC method; (2) the effect of the vibration term on the calculating time is dependent upon the integration of the potential matrix, in which a calculation including only the ground state gives remarkably good results.
DIRECT OBSERVATION AND RECORDING OF TWO-WAVE MIXING OF ps LIGHT PULSES IN Ce:KNSBN CRYSTAL
Authors: SHE WEI-LONG  , LI QING-XING  , YU ZHEN-XIN  , GAO ZHAO-LAN  , MO DANG  , ZHU DE-RUI  ,   (1)中山大学激光与光谱学研究所,广州510275; (2)中山大学物理系,广州510275
Published: December 2020

Two-wave mixing is realized in Ce doped KNSBN crystal by using ps light pulses with a repetition rate of 82 MHz. The experimental results recorded directly by using a streak camera and an explanation are presented.
STUDY ON GRAIN GROWTH KINETICS OF THIN FILMS BY MEANS OF QUASI-STATE MEASUREMENT OF RESISTIVITY
Authors: WANG XIAO-PING  , ZHAO TE-XUE  , JI HANG  , DONG YI  , BIAN BO  ,   中国科学技术大学物理系,合肥230026
Published: December 2020

A method for studying grain growth kinetics of thin films by means of quasi-state measurement of films resistivity is proposed. Pd films is prepared by d c sputtering in ultra-high vacuum, and relationship between resistivity of Pd films and annealling time is measured at different tempertures The change of grain size of Pd films can be calculated by using the two-fluid model and can be compared with results of TEM. It is found that annealling temperature plays an important role in grain growth process and grain growing curve is imitated. The experiment results indicate that grain growth process is thermal activated and the activation energy is about 0. 53eV.
DEPENDENCE OF THE DEFORMATION IN DISSIPATIVE QUANTUM TUNNELING SYSTEMS ON THE DIMENSION OF THE BATH
Authors: SHI YUN-LONG  , NIE YI-HANG  , CHEN HONG  , WU XIANG  ,   (1)同济大学物理系,上海200092; (2)雁北师范学院物理系,大同037000
Published: December 2020

The deformative effect of phonon states of the bath in a dissipative quantum tunneling system is studied by perturbation and a variational approach. We find that the deformative effect depends on the dimension of the bath. It increases as the dimension is reduced on one hand. On the other hand,it gives more stronger influence on the quantum tunneling system for a lower-dimensional bath.
ON THERMAL FLUCTUATIONS IN A JOSEPHSON-FLUXON OSCILLATOR
Authors: WANG QIANG-HUA  , YAO XI-XIAN  ,   南京大学物理系,南京210008
Published: December 2020

Thermal fluctuations in a Josephson-fluxon oscillator are considered with emphasises on the stochastic dynamics of fluxon and the non-trivial continuum-mode excitations. Analytical expressions for the radiation line-width of the oscillator are derived from perturbation theory and standard stochastic process theory. The averaged kinetic energy of a low-velocity fluxon is shown to be kBT/2. The continuum excitations are explored in the framework of the inverse scattering transform approach. The averaged energy per wave mode turns out to be kBT,and this justifies the adiabatic approximation applied in the fluxon stochastic dynamics.
FAR-INFRARED SPECTRA OF NATURALLY OCCURRING FeS2(Pyrite)
Authors: MAO NIAN-XIN  , HUANG YE-XIAO  , LU WEI  , YE HONG-JUAN  , SHEN XUE-CHU  , HU ZHI-HONG  , LUO AN-XIANG  ,   (1)南京大学地球科学系,南京210008; (2)中国科学院上海技术物理研究所红外物理国家重点实验室,上海200083
Published: December 2020

The far-infrared reflectance and transmittance spectra of natural FeS2(Pyrite) at room and low temperatures are reported in this artical. The spectral structure and the physical origin are discussed in detail. Through our research we found that the plasmon reflectance edge at low frequency of room temperature reflectance spectra of FeS2(Pyrite) samples have a close relation with the natural impurity: PbS(Galena) in samples. We use the reflectance spectra at room temperature of FeS2(Pyrite) and PbS (Galena) mineral single crystals as basic spectra to reproduce the experimental spectra of different samples in various proportions. the x values we obstained form it not only reflect the relative quantities of PbS (Galena) impurity, but also have positive correlation with the noble metal: Au(Gold) indirectly. This may have some applications in mineral formation research.
ON THE SATURATION PROPERTIES AND THE LIQUID-GAS PHASE TRANSITION OF FINITE NUCLEAR MATTER WITH GOGNY INTERACTION
Authors: CAO FU-GUANG  , YANG SHAN-DE  ,   (1)吉林大学理论物理中心,长春130023; (2)吉林大学物理系,长春130023
Published: December 2020

The Hill-Wheeler formula is applied to deriving the equation of state for finite nuclei with the Gogny effective interaction in the framework of Hartree-Fock theory. The reasonable zero-temperature saturation properties is obtainde, and the critical temperature for liquid-gas phase transition of finite nuclei is found to be around 12 MeV. In addition it is found that the phenomenological formula for surface energy used widely is not available when the density is far away from the normal nuclear density, and a new formula is suggested.
STUDY OF RAMAN SPECTRA FOR CRYSTALS WITH SPACE GROUP P3121(D34) ( Ⅱ )——THE RAMAN SPECTRA OF a-QUARTZ
Authors: XIA HAI-RUI  , LI LI-XIA  , CHEN CHEN  , QIN ZI-KAI  ,   (1)山东大学实验中心,济南250100; (2)山东大学物理系,济南250100
Published: December 2020

Based on the symmetry of the space group P3121(D34), we consider that there are six molecules per primitive cell in a-quartz, and the constants of the primitive cell should be c = 1. 0788 nm and a = 0. 4904nm This point of view has been confirmed by our experiment.
STUDY ON THE ADSORPTION OF HYDROGEN ON SUPPORTED-METAL SURFACES
Authors: XIE JIAN-JUN  , ZHANG TAO  , LU WEN-CHANG  ,   (1)复旦大学物理系,上海200433; (2)河南师范大学物理系,新乡453002
Published: December 2020

The adsorption properties of hydrogen on the supported-metal surfaces are investigated using the Green function method within the framework of tight-binding approximation. The adsorption energy ΔE and the adatom state energy Ead, for hydrogen adsorption on Pt/ZnO, Cu/ZnO and Ni/ZnO composite systems are calculated by employing the self-consistent An-derson-Newns adsorption theory. The effects of the metal-support interaction on the adsorption properties of hydrogen on supported-metal surfaces are discussed. It is found that the stronger the metal-support interaction is, the less the adsorption energy and charge transfer for H on Pt(Cu,Ni)/ZnO become. The metal-support interaction impedes hydrogen adsorption on the metal surfaces. This effect becomes weak as the metal film grows thick.
DEEP LEVELS IN STRAINED Si AND Ge
Authors: QIAO HAO  , XU ZHI-ZHONG  , ZHANG KAI-MING  ,   复旦大学物理系,上海200433
Published: December 2020

Deep levels of vacancy and substitutional impurity atoms in strained Si or Ge grown on alloy substrates are investigated. The band structures of strained bulk are calculated by using the empirical tight-binding method. The method of Green's function has been used to calculate the defect levels. The results show that the triplydegenerate p-like T2 level of defect in bulk Si or Ge splits into two levels due to the strain. The value of splitting increases with strain increasing. Owing to the strain,the valence band maximum of Si or Ge shifts upward, hence some deep levels in the bulk might transform to resonant ones.
M?SSBAUER EFFECT RESULTING FROM SUPERSONIC SOLITONS IN QUASI-ONE-DIMENSIONAL ORGANIC MOLECULAR CRYSTALS
Authors: PANG XIAO-FENG  ,   中国科学院国际材料物理中心,沈阳110015;西南民族学院物理系,成都610041;中国高等科学技术中心世界实验室成员
Published: December 2020

In this paper,the properties of the M?ssbauer effect resulting from supersonic solitons generated by the localized fluectuation and the deformation of structure in quasi-one-dimensional organic molecular crystal at temperature T≠0 and with non-linear vibration of molecular chains have been studied in the case of γ-photons emission from the γ-active nucleus. The expression for the time-dependentr γ radiation M?ssbauer transition probability is presented, and some interesting
PICOSECOND LUMINESCENCE DECAY MEASUREMENT FOR POROUS Si AND ANALYSIS OF EMISSION MECHANISM
Authors: ZHANG XIAO-RONG  , BAO XI-MAO  , YAN FENG  , GAN CHANG-MING  , CAI ZHI-GANG  , HUANG XU-GUANG  , ZHOU SHI-YING  ,   (1)南京大学声学研究所,南京210008; (2)南京大学物理系; (3)中山大学超快速激光光谱学国家重点实验室,广州510275
Published: December 2020

Luminescence spectra, picosecond decay and Fourier transform infrared spectroscopy measurements show that there are two independent emission mechanisms in the spontaneously oxidized porous Si. One is determined by the quantum confinement effect , the other is produced by the oxidation.
INVESTIGATION OF CHARACTERISTICS OF WIDE-BAND FEMTOSECOND LASER SUPERCONTINUUM
Authors: ZHANG WEI-LI  , ZHANG RUO-BING  , WANG QING-YUE  ,   天津大学精密仪器工程系,天津300072
Published: December 2020

The characteristics of supercontinuum in various nonlinear materials has been investigated with high-gain, Low-dispersion femtosecond amplifier. The wide-band femtosecond laser supercon-tinuum has been obtained.
INFLUENCE OF TRIPLE JUNCTION ON THE FRACTURE BEHAVIOR IN COPPER-BISMUTH TILT TRICRYSTAL
Authors: WANG JING  , WU XI-JUN  , WANG YING  ,   中国科学院固体物理研究所,合肥230031
Published: December 2020

The fracture behavior of tilt Cu-Bi tricrystals were studied and a contrast with that of Cu-Bi bicrystals was made. The results indicate that the triple junction affected the fracture behaviors of Cu-Bi tricrystals and made a grain boundary exhibit different fracture modes in bicrystal and tricrystal,The high internal stress near triple junction produced incompatibility of plastic deformation, as well as appearing of inhomogeneity of platic glide and lattice rotation. These are discussed by calculating stress field near triple junction.
ELIMINATION OF INTERFACIAL BORON SPIKES IN Si MOLECULAR BEAM EPITAXY BY HYDROGEN PASSIVATION TREATMENT OF Si (100) SUBSTRATE
Authors: WEI XING  , GONG DA-WEI  , YANG XIAO-PING  , LU HONG-QIANG  , CUI QIAN  , SHENG CHI  , ZHANG XIANG-JIU  , WANG XUN  , WANG QIN-HUA  , LU FANG  , SUN HENG-HUI  ,   (1)复旦大学物理系,上海200433; (2)复旦大学应用表面物理国家重点实验室,上海200433
Published: December 2020

A stable hydrogen-terminated Si (100) surface was obtained by using a modified mothed. The Si (100) surface was hydrogen passivated during the ex-situ HF-dip followed by the in-situ low-temperature desorption of physisorbed residues. It was found that this procedure is very effective to eliminate the boron spike at the Si MBE layer/p-Si substrate interface. The origon of the boron spike is also discussed.
THE RELATIVE FERMI LEVEL POSITION AND THE ELECTRON-PHONON COUPLING OF YBa2Cu3Ｏ７－δ STUDIED BY FEMTOSECOND TRANSIENT REFLECTIVITY
Authors: XIONG GUANG-CHENG  , ZOU YING-HUA  , XIA ZONG-JU  , YUAN PING  , LIAN GUI-JUN  , LI JIE  ,   北京大学人工微结构与介观物理国家重点实验室
Published: December 2020

The femtosecond pulsed laser and pump-probe method have been used to measure the transient change of reflectivity of YBa2Cu3Ｏ７－δ(δ=0.0, 0.1, 0.4 and 0.8) thin films. From the experimental curves the transient changes are found to be very different for samples with different oxygen content. The sign of the changes can be reversed as decreasing the oxygen content. It may be attributed to the changes of energy band structure near the Fermi level. After fitting the experimental data, we reveal that the electron-phonon coupling in the sample of δ=0.4 is much weaker than high Tc(δ=0.0) sample.
A STUDY OF SURFACE-ENHANCED ENERGY TRANSFER EFFECT BETWEEN MOLECULES
Authors: PAN DUO-HAI  , MA YONG-HONG  ,   陕西师范大学物理系,西安710062
Published: December 2020

The energy transfer effect between molecules adsorbed on rounghened silver surface has been investigated both theoretically and experimentally. The theoretical results indicate that when the emission frequency of the donor and the adsorption frequency of
双光子双模激光的朗之万理论
Authors: HU XIANG-MING  ,   华中师范大学应用物理研究所,武汉430070
Published: December 2020

Mode coupling of a two-photon two-mode laser operating near above threshold is discussed with Langevin quantum theory. Characteristics of the coupling shows not only the mutual enhancement of the two modes, as well as the enhancement of mode 2 with suppre
RELATIVISTIC MULTICONFIGURATION CALCULATION OF FINE-STRUCTURE ENERGY LEVELS AND TRANSITIONS FOR Cu-LIKE Au50+
Authors: TAN MING-LIANG  , ZHU ZHENG-HE  , ZHAO YONG-KUN  , CHEN XIAO-FENG  ,   (1)成都科技大学原子与分子物理研究所; (2)高温高密度等离子体物理重点实验室
Published: December 2020

The fine-structure energy levels and transition parameters of Cu-like Au50+ have been calculated by using the relativistic multi-configuration method(GRASP 2,1992) with the corrections of finite nuclear size, Breit and QED. The results obtained are in good agreement with the experimental data available and better than those of the previous calculations. It can be concluded that the QED correction should be taken into account further, which greatly improves the accuracy of the calculated 4s—4p transition wavelengths.
STUDY THE INTERDIFFUSION IN AMORPHOUS Nb/Si MULTILAYER
Authors: ZHANG MING  , YU WEN  , ZHANG JUN  , ZHANG YUAN-YI  , WNAG WEN-KUI  ,   (1)中国科学院物理研究所; (2)中国科学院物理研究所;中国科学院国际材料物理中心
Published: December 2020

The amorphous Nb/Si multilayers were prepared for the interdiffusion study. The temperature dependent effective interdiffusion at low temperature in amorphous Nb/Si multilayer was obtained using in-situ XRD technique. The smaller pre-exponential factor for diffusion coefficient in amorphous Nb/Si multilayer is explained by the trap-retarded diffusion mechanism. In this model, the atomic vibration frequency v is substituted by the average characteristic atomic vibration frequency v because of the presence of defect traps.
ONE-DIMENSIONAL RANDOM SUCCESSIVE NUCLEATION GROWTH MODEL
Authors: WU FENG-MIN  , WANG YAN  , WU ZI-QIN  ,   (1)浙江工业大学; (2)中国科学技术大学基础物理中心
Published: December 2020

A computer simulation model of one-dimensional random successive nucleation growth is presented. A series of patterns and their fractal dimensions are obtained for three near-neighbor conditions. The simulated structures are similar to those of porous silicon. The properties of the D-X curve and the critical threshold of the cluster change from fractal to uniform structure are also discussed briefly.
INFLUENCE OF ENVIRONMENTAL RADIATION ON LIFETIMES OF STARK STATES IN HIGHLY EXCITED ATOM
Authors: FANG DA-WEI  , XIE WEI-JUN  , ZHANG SEN  ,   (1)九江师范专科学校物理系; (2)浙江大学物理系; (3)中国计量学院光电子技术研究所
Published: December 2020

The populations of n=17,m=0 Stark states of sodium atom in static electric fields have been obtained by two step excitation using tunable lasers. The lifetimes of some selected Stark states and the influences of blackbody radiation on the lifetimes were measured by using delayed electric field ionization. The measured data were compared with the calculated values. The experimental and theoretical results exhibit following behaviours: The total rates of stimulated emission and absorption transitions induced by environmental radiations are of the same order of magnitude in comparison to those of spontaneous transition for the observed n=17 Stark manifold states at room temperature. And this effect is more remarkable for longer lived states. It, along with the effect of the Stark mixing of l sublevels, will reduce the differences among lifetimes of Stark states in a manifold.
SCANNING TUNNELING MICROSCOPIC OBSERVATION OF GRAPHITE SURFACE DAMAGE INDUCED BY GOLD IONS BOMBARDMENT(Ⅱ)
Authors: WANG YU-GANG  , KANG YI-XIU  , ZHAO WEI-JIANG  , YAN SHA  , YAN JUN-JUE  , YANG WEI-SHENG  , ZAI PENG-JI  , TANG XIAO-WEI  ,   (1)北京大学物理系; (2)北京大学重离子物理研究所; (3)中国科学院高能物理研究所
Published: December 2020

The individual damage on high oriented pyrolytic graphite surface induced by gold ions of 530keV—4.5MeV was studied with scanning tunneling microscope. The hillock-like damage was observed and measured and then the average diameters of the hillocks were obtained. In terms of a modified nonlinear thermal spike model, the diameters of the damage were calculated and the results fit well with the experimental data. The possible mechanism of damage formation is discussed.
STRESS ON THE Ni,Pd AND Pt SURFACES
Authors: FAN XI-QING  , WAN JUN  , SHEN SAN-GUO  ,   郑州大学物理工程学院
Published: December 2020

The semiempirical modified embedded atom method has been applied to calculate the surface stress on the low index surfaces of fcc metals Ni,Pd and Pt,and the results are in agreement with that of the first principle calculation.The surface stress on fcc(110) surface along the [110] direction is about twice as large as in the [001] direction;and this indicates that the anisotropy of the surface stress is a characteristic of (110) surface of fcc metals.In addition,the magnitudes of the surface stresses on Pd and Pt(100) surfaces have been predicted.
CALCULATION OF THE ELECTRONIC CORRELATION-ENERGY IN HELIUM ATOMS BY MEANS OF B SPLINE TECHNIQUE
Authors: QIAO HAO-XUE  , RAO JIAN-GUO  , LI BAI-WEN  ,   中国科学院武汉物理与数学研究所波谱与原子分子物理国家重点实验室
Published: December 2020

The B spline method for calculating the correlation energy of helium atoms is proposed.The result is compared with that by Slater basis functions.The virtue defect and practicability of B spline technique are analysed.It is shown that the B spline technique can be used widely in the calculation of electronic interaction.
DIELECTRONIC RECOMBINATION AS TWO INDEPENDENT PROCESSES
Authors: WANG JIAN-GUO  , ZOU YU  , CHANG TIE-QIANG  ,   北京应用物理与计算数学研究所
Published: December 2020

In this paper,dielectronic recombination process is proposed as two independent processes resonant capture(inverse Auger) process and radiative decay process,which can be used- conveniently in the varied plasmas environments.Through the quantum defect theory,a simplified- analytical formula is introduced to calculate the Auger rate and the theoretical results have been- compared with a simplified relativistical configuration interaction calculation.Finally,a method for- applying the formula to the average atom model is given.
STRUCTURAL AND MAGNETIC PROPERTIES OF Gd Fe Co Ga COMPOUNDS WITH 2∶17 TYPE STRUCTURE
Authors: ZHANG LI-GANG  , ZHANG SHAO-YING  , ZHANG HONG-WEI  ,   (1)武汉冶金科技大学基础科学系; (2)中国科学院物理研究所和凝聚态物理中心磁学国家重点实验室
Published: December 2020

The compounds of Gd2（Fe1-xCox）15Ga2(0≤x≤1.0) and Gd2（Fe0.8Co0.2）17-yGay(0≤y≤8) were prepared by arc melting. Their structure and magnetic properties have been studied by means of X ray diffraction and magnetic measurements. Experimental results show that single phase compounds with the 2∶17-type structure were obtained for all samples. It was found that the unit cell volume of Gd2（Fe1-xCox）15Ga2 compounds decreases, while the Curie temperature Tc increases monotonously with increasing Co concentration. The saturation magnetization Ms at 1.5K first increases with increasing x, then decreases, showing a value of maximum at x=0.2. For Gd2（Fe0.8Co0.2）17-yGay,the unit cell volume increases, the Curie temperature and the saturation magnetization at 1.5K decrease monotonously with increasing Ga content. The substitution of Co or Ga for Fe in Gd2Fe17 compounds results in a change of magnetocrystalline anisotropy of Fe or Co sublattice from easy plane to easy c-axis at room temperature. This is likely related to the preferential site occupancy of Ga atom.
APPLICATIONS OF THE THEORY OF RELATIVISTIC THERMODYNAMICS TO THE SCHWARZSCHILD MATTER SYSTEM IN THE GRAVITATIONAL FIELD
Authors: LIU LU-XIN  ,   大连理工大学物理系
Published: December 2020

The matter system in the Schwarzschild gravitational field is discussed in terms of the formal ism of the relativistic thermodynamics. The stellar structure equation is obtained, and both the statical and the moving particle systems are investigated. The solutions derived agree with the Newton theories under the condition of classical approximation.
A METHOD FOR CALCULATING THE FORM SCATTERING FUNCTION OF NONSPHERICAL PARTICLE
Authors: XU MAN-HUA  , WEI MING-JIAN  ,   武汉工业大学数理系
Published: December 2020

In measuring the particle-size distribution by small angle X-ray scattering the particle form must be known.In general the form of particles considered to be spherical ,but in practice, the form of particles was very complexity.We statistcally separate the forms of particles into sphere-like; flat-like and rod-like ones. The general method for calculating the form scattering function has been given, and we have calculated the form scattering function for sphere-like particles, and given an adjustable parameter δ that can be used in general analysis.
INVESTIGATION OF (1-x)PMN-xPT FERROELECTRIC REFRIGERATION CERAMICS
Authors: XIAO DING-QUAN  , WANG YONG-CHUAN  , ZHANG RONG-LONG  , PENG SHANG-QIANG  , YANG BIN  , ZHU JIAN-GUO  , ZHANG WEN  , WANG HONG-TAO  ,   四川大学材料科学系，成都  610064
Published: December 2020

In recent years, the electrocaloric effect (abbr. ECE) of dielectrics has attracted attention for ferroelectric refrigerating application. The fundamentals of ferroelectric refrigeration and the expressions of three types of ECEs, i.e., linear, quadratic and field-induced first-order phase transition electrocaloric effects, are presented in this paper. The ECE properties of (1-x)PbMg1/3Nb2/3O3-xPbTiO3［abbr. (1-x)PMN-xPT］ ferroelectric ceramics(x=0.08, 0.10, and 0.25 respectively) at room temperature were measured and analyzed. It is found that the large electrocaloric effect of (1-x)PMN-xPT ferroelectric ceramics about room temperature is due to the electric-induced first-order phase transition and linear electrocaloric effects, and these ceramics could be used in ferroelectric multi-stage refrigeration.
ION RADIATION DAMAGE OF C60 FILMS
Authors: ZOU YUN-JUAN  , YAN HUI  , CHEN GUANG-HUA  , JIN YUN-FAN  , YANG RU  ,   (1)北京工业大学应用物理系,北京 100022; (2)中国科学院近代物理研究所,兰州 730000
Published: December 2020

The C60 films have been implanted with 120—360 keV H,N, Ar and Mo ions by using a 200 keV heavy ion accelerator. The samples were investigated by Raman spectra. The results showed an exponential decrease of intensity for 1469 cm-1 line depending on the kind of ions and dose. There appeared a structural transformation of C60 to amorphous carbon at certain doses, which is correlated to the nuclear energy transfer. H ions implantation resulted in an asymmetrical broadening of 1469 cm-1 line, which is due to the electronic energy transfer.
SELECTIVE RULES FOR THE RAMAN SPECTRUM OF α-HELICAL PROTEIN MOLECULES
Authors: YAN  XUN-LING  , DONG  RUI-XIN  , WANG  BO-YUN  , HU  HAI-QUAN  , XU  BING-ZHEN  ,   山东聊城师范学院物理系，聊城  252059
Published: December 2020

The selective rules for the Raman spectrum of α-helical protein molecules are given on the basis of the Hamiltonian presented and the laser-Raman spectrum measured on the metabolically active cells.
STUDY OF BEAM UNIFORMITY METHODS IN INDIRECT-DRIVEN LASER FUSION
Authors: ZHANG BIN  , Lv  BAI-DA  , XIAO JUN  ,   四川大学激光物理与化学研究所，成都  610064
Published: December 2020

Some methods for beam uniformity,such as random phase plate,partially coherent light and “two in one” used in indirect-driven laser fusion,have been studied and analyzed numerically by using the generalized diffraction integral theory.The intensity distributions at the entrance hole and on the wall of a cylindrical hohlraum have been given.The results are useful for the choice of laser uniformity schemes in indirect-driven laser fusion.
THE PHYSICAL MECHANISM OF PROMOTED AMORPHOUS CRYSTALLIZATION BY MULTIPLE ULTRASHORT ELECTROPULSING
Authors: CHAO YUE-SHENG  , XIAO SU-HONG  ,   东北大学理学院,沈阳  110006
Published: December 2020

Amorphous Fe78Si9B13 specimens have been treated by multiple ultrashort electropulsing with a high current density. The treatment conditions were：1.Keeping the pulse frequency and acting time constant, the current density uninterrupted increases. 2.The pulse frequency increases continuously under constant current density and acting time. The crystallized structures of specimens after electropulsing were investigated by Mssbauer spectroscopy. The results show that the nucleation rate of base metal phase in amorphous specimens increases obviously with the increase of current density and pulse frequency.
ELECTRON THEORY OF MECHANICAL PROPERTIES OF INTERMETALLICS IN Ti-Al ALLOY SYSTEM
Authors: LI WEN  , CHEN DAI-MIN  , GUAN ZHEN-ZHONG  , ZHANG RUI-LIN  ,   (1)吉林大学材料科学系，长春  130023; (2)中国科学院长春光学精密机械研究所，长春  130022
Published: December 2020

The mechanical properies of intermetallics in Ti-Al alloy system are studied systematically from the view point of valence electron by the empirical electron theory (EET). First, according to the basic thinking of the EET, space topology of valence electron structure is modelled, and the embrittlement nature of intermetallics in Ti-Al system is concisely brought to light. Second, the valence electron structure symmetry factor α, which has a good relationship to the plasticity is proposed from the model, and the embrittlement criterion is summed up. Finally, the empirical relation between valence electron structures and mechanical properties can be established.
THE REACTION TO THE SCHWARZSCHILD SPACE-TIME BY THE HAWKING EVAPORATION
Authors: ZHAO REN  , LIU LIAO  ,   (1)北京师范大学物理系，北京  1000875; (2)雁北师范学院物理系，大同  037000
Published: December 2020

For the black hole having Hawking radiation, it must have effect on the space-time metric (the so-called back-reaction). By combination of the result from themodynamical approach with the back-reaction of the black hole and the semiclassical Einstein equation, we get the modified Schwarzschild space-time metric. This method is much more simple and convenient than that of Jork's.
Study on the Magnetocaloric of Alloy Gd3Al2-xGax
Authors: Wang Dun-Hui  , Yin Jin-Hua  , Tang Shao-Long  , Shen Ya-Tao  , Du You-Wei  ,   南京大学物理系，固体微结构物理国家重点实验室，南京　210093
Published: December 2020

A series of Gd3Al2-xGax alloys over a composition range (x=0,0.1,0.3,0.5) were prepared from high purity Gd, Al, and Ga by arc melting under purified argon atmosphere on a water-cooled copper crucible, then annealed in vacuum at 1073 or 1173K for 36h. The X-ray diffraction pattern indicated that these alloys were single phase of Zr3Al2-type structure. Magnetization isotherms at different tempertures of these alloys were measured between 180 and 300K under the magnetic field up to 1.12106A/m using vibrating sample magnetometer. We found that magnetic entropy change of Gd3Al2-xGax(x=0.1,0.3,0.5) was larger than that of Gd3Al2, and the s of change (about 3.0J/kgK) of Gd3Al2-xGax(x=0.1) was observed at 280K under a magnetic field of 1.12106A/m.
Giant Magneto-Impedance Effect in Amorphous CoFeNiNbSiB Alloy Ribbon
Authors: Zhang Rong  , Xu Yu-Sheng  ,   苏州大学物理系，苏州 215006
Published: December 2020

The giant magneto-impedance (GMI) effects in amorphous Co70Fe4.5Ni4Nb1Si12.5B8 alloy ribbon have been observed. It is shown that the GMI effects increase with driving current frequency and an appropriate annealing can enhance the effect. A large MI ratio of about 120% in the as-cast sample and a ratio of about 400% in a suitably annealed sample have been measured at 5MHz.
FROM SCHWARZSCHILD BLACK HOLE TO KERR-NEWMAN BLACK HOLE
Authors: LIU WEN-BIAO  , LI XIANG  ,   北京师范大学物理系，北京  100875
Published: December 2020

A falling-in physical particle in metric and electromagnetic tensor field of Schwarzschild and Kerr-Newman black hole is studied.It is concluded that the physical particle will not make the outer horizon smaller.This is coincident with the area theorem.It is well known that δA≥0 andδκ≤0 are the necessary condition for changing from nonextremal to extremal Kerr-Newman black hole.We demonstrate that the surface gravity (temperature) of a Kerr-Newman black hole cannot be reduced to zero in a finite sequence of physical interactions.This is coincident with the third law of black hole thermodynamics.We also consider the trend of area change in the evolution of near-extremal black hole.The effect of negative heat capacity and the entropy renormalization are discussed.
Magnetic Properties of Nanostructured SmCo/FeCo Multilayers
Authors: Liu Xiang-Hua  , Yan Ge  , Cui Li-Ya  , Zhou Shao-Xiong  , Wang Chong-Yu  , Zheng Wu  , Wang Ai-Ling  , Chen Jin-Chang  ,   (1)钢铁研究总院国家非晶微晶合金工程技术研究中心，北京 100081; (2)首都师范大学物理系，北京 100037
Published: December 2020

The dependence of reduced remanence (Mr/Ms) and coercivity of Sm22Co78/Fe65Co35 bilayer and Sm22Co78/Fe65Co35/Sm22Co78 triple-layer films on Fe65Co35 soft-magnetic layer thickness d, was systematically investigated. All the hysteresis loops of the films exhibited a single-phase behavior, reflecting a strong exchange coupling between soft-and hard-magnetic phase. Mr/Ms showed a monotonic increase with increasing Fe65Co35 thickness d, and the coercivity would show a peak with increasing d. From the plot of M versus applied field H, it is shown that the positive profile decreases and the negative interaction profile increases with the increase of interfaces between soft-and hard-layers.
OUTPUT FEEDBACK SYNCHRONIZATION OF A CHAOTIC ARNEODO SYSTEM
Authors: LIU FENG  , MU ZHAO-LI  , QIU ZU-LIAN  ,   西安交通大学自动控制工程系，西安  710049
Published: December 2020

This paper presents a linear output feedback synchronization approach for a chaotic Arneodo system. Based on the linear stability theorem, a sufficient condition of asymptotic synchronization is given, and the boundary of the range of the output feedback parameter is given also. Finally, a computer simulation is given to demonstrate the effectiveness of the method.
THEORETICAL ANALYSIS OF THE MODEL OF FLYER-THREE-STEP-TARGET WITH LASER DRIVING:USING IN ABSOLUTE MEASUREMENT OF EQUATION-OF-STATE
Authors: HUANG XIU-GUANG  , LUO PING-QING  ,   (1)北京应用物理与计算数学研究所，北京  100088; (2)上海激光等离子体研究所，上海  201800
Published: December 2020

We present the numerical calculation of the model of aluminum flyer-vacuum-target with high power laser driving.The results show that the parameters of laser and target's structure have great effects on the state of flyer and the character of shock-waves in the target.If we select the parameters of laser and target's structure reasonably, we can achieve approximately symmetric impact between flyer and target;moreover,the shock-wave in the target has a stable area with a certain spatial width.So,if we choose the three-step-target with a suitable thickness,we can approach an absolute measurement of equation-of-state.
Low-Temperature Longitudinal Magnetoresis-Tance Effect in Ag2+δTe Thin Films
Authors: Liang Bing-Qing  , Wang Yin-Jun  , Chen Xi  ,   中国科学院物理研究所与凝聚态物理中心磁学国家重点实验室，北京 100080
Published: December 2020

Abnormal longitudinal magnetoresistance (LMR) in self-doped silver telluride films at low temperature is investigated. In the Ag2.1Te films, we observe the large negative LMR and the multipeaks in magnetic resistivity ρand LMR that strongly depend on doping concentration and temperature. The abnormal MR behavior, which might result from the complex structure and texture of the films, is explained by means of Toyozawa model.
OBSERVERS FOR A CLASS OF CHAOTIC SYSTEMS
Authors: YANG XIAO-SONG  ,   重庆邮电学院非线性系统研究所，重庆  400065
Published: December 2020

In this paper the design of observers of a class of chaotic systems is discussed. By means of scalar nonlinear signal one can construct a control law to implement the synchronization between the investigated chaotic system and its observer.
ORIENTATIONAL POPULATION AND RELAXATION BEHAVIOR OF C60 MOLECULES BET WEEN ORDER-DISORDER PHASE TRANSITION AND GLASSY TRANSITION
Authors: CAO WAN-QIANG  , CHENG YUAN-FA  , LIU JUN-DIAO  , XING GUO-KUEN  ,   (1)湖北大学物理学与电子技术学院，武汉  430062; (2)惠州大学物理系，惠州  516015
Published: December 2020

The site occupancies of orientational angle 98° and 38° of C60 mole cules versus temperature is investigated by extremal dynamic model in the temper ature range between order-disorder phase transition and glassy transition.The oc cupancy of orientational angle 38° calculated by the model are precisely coinci dent with reported experimental values at T=85K,90K and 260K,respectively.The mo re precise agreement and second-order differential to temperature of site occupa ncy predict that the glassy transition point is at 84K.The relaxation process of two orientational states from non-equilibrium deduced by the new model is relat ed to the non-exponent factor β in KWW equation,and overall relaxation of C60 crystal is mainly attributed to the relaxation of the lowest energy le vel.Considering two energy levels and their energy difference,the calculated β value 0.9495 is near the experimental value 0.94±0.02.
STUDY ON SEMICONDUCTING YBCO THIN FILM AND CHARACTERISTICS OF BOLOMETER
Authors: LIU JING-HE  , SUN QIANG  , LIU XIANG-DONG  , XING HONG-YAN  , LI JIAN-LI  , LI GUO-ZHEN  , HUANG ZONG-TAN  , HUANG CHENG-CAI  , LI DAN  , HUANG JIANG-PING  ,   (1)长春光学精密机械学院，长春  130022; (2)昆明物理研究所，昆明  650023
Published: December 2020

We have studied the semiconducting property of the Y1Ba2Cu 3O7-δ(δ≥05, abbreviated YBCO) thin film which is depo sited on Si substrate and the characteristics of the bolometer using the film to detect IR radiation. We measured TCR merit and Hall coefficient and analyzed th e microstructure and the responsive characteristics of the YBCO semiconducting t hin film through XRD and Raman spectrum. We believe that the thin film is a new sensing material which can be applied to uncooled infrared focal plane bolometers.
EFFECT OF GRAVITY ON THE WETTING BEHAVIOR OF MOLTEN GaSb DROP
Authors: WANG CHAO-YING  , ZHAI  GUANG-JIE  , WU LAN-SHENG  , MAI ZHEN-HONG  , LI HONG  , ZHANG HAI -FENG  , DING BING-ZHE  ,   (1)中国科学院金属研究所，沈阳  110015; (2)中国科学院物理研究所，北京  100080
Published: December 2020

The wetting behavior of molten GaSb drops on the substrates of GaP,BN or GaAs in space has been investigated using Chinese recovered satellite.The interaction at the interface of the molten drop and the substrate has been analyzed and compared with the results on the earth.The experiment results show that the gravity has an effect on the wetting behavior of GaSb molten drop.The contact angle of GaSb drop with GaP and BN substrates in space is larger than that on the earth.The morphology of the interface between the concreted drop and the substrate indicates that on the earth the interaction at the liquid/solid interface is strong and a wider transition region exists.It is concerned that the gravity convection is of benefit to the transfer of matters.The experiment results also show that the morphology of the samples concreted in space is more uniform than that on the earth.
DESIGN OF A KIND OF FRACTAL FILM SETS WITH LOW-REFLECTION
Authors: LI YAN  , HE DA-REN  ,   扬州大学物理系，扬州  225002
Published: December 2020

This paper discusses the design of a kind of fractal film set showing good absorption for electromagnetic waves. Based on a simplified model, we have calculated analytically the reflectivity of the film set, and obtained a group of criterions for selection of suitable materials for the set layers so as to decrease the reflectivity. Numerical simulations have been done to obtain the reflectivity of some film sets constructed by ideal or practical materials selected according to the criterions. The results show that the reflectivity of the set decreases when the total degree number of the fractal increases. The lowest reflectivity obtained is 0.01.
CARBON FILM DEPOSITED BY MASS-SELECTED LOW ENERGY ION BEAM TECHNIQUE AND ION BOMBARDMENT EFFECT
Authors: LIAO MEI-YONG  , ZHANG JIAN-HUI  , QIN FU-GUANG  , LIU ZHI-KAI  , YANG SHAO-YAN  , WANG ZHAN-GUO  , LEE SHUIT-TANG  ,   (1)香港城市大学物理和材料科学系，香港; (2)中国科学院半导体研究所半导体材料科学实验室，北京  100083
Published: December 2020

By mass-selected low energy ion beam deposition, amorphous carbon film was obtained. X-ray diffraction, Raman and Auger electron spectroscopy depth line shape measurements showed that such carbon films contained diamond particles. The main growth mechanism is subsurface implantation. Furthermore, it was indicated in a different way that ion bombardment played a decisive role in bias enhanced nucleation of chemical vapor deposition diamond.
POLARONS AND BIPOLARONS IN MIXED HALIDE MX COMPOUNDS
Authors: WEI JIAN-HUA  , XIE SHI-JIE  , MEI LIANG-MO  ,   山东大学物理系，济南  250100
Published: December 2020

Polarons and bipolarons in mixed halide MX compounds were studied in the frame work of the two-band extended Peierls-Hubbard model.Different from the isolated MX chains,it was found that the segments tend to select impurities in mixed halide compounds.Then the charge confinement and the effect of electron-electron interactions were investigated.Finally the properties of impurities in mixed halide compounds with spontaneous charge transfer were also discussed.
RAMAN SCATTERING FROM InAs NANOCRYSTALS EMBEDDED IN SiO2 THIN FILMS
Authors: ZHU KAI-GUI  , SHI JIAN-ZHONG  , SHAO QING-YI  ,   (1)Data Storage Institute,National University of Singapore,Singapore  119260; (2)北京大学电子学系，北京  100871; (3)中国科学技术大学结构分析开放研究实验室，合肥  230026
Published: December 2020

Raman scattering from InAs nanocrystals embedded in SiO2 thin films has been measured and studied. Raman spectra of InAs nanocrystals have a similar feature with that of bulk InAs crystal. Broadened and red-shifted Raman scattering peaks were observed from the nanocrystals; this has been attributed to the phonon confinement effect. A compressive stress in the interface between InAs nanocrystals and the SiO2 matrix was also taken into account to interpret the red shift.
A METHOD FOR COMPUTING LYAPUNOV EXPONENTS SPECTRA WITHOUT REORTHOGONALIZATION
Authors: LAI JIAN-WEN  , ZHOU SHI-PING  , LI GUO-HUI  , XU DE-MING  ,   (1)上海大学通信与信息工程学院，上海  201800; (2)上海大学物理系，上海  201800
Published: December 2020

We present a method for the computation of Lyapunov exponents without reorthogon alization. In the low dimension of system(n<5) ,the equations needed in present algorithm is less than those in normal methods such as QR, SVD etc. This method is applicable to both discrete systems and continuous systems, and is still valid when the Lyapunov spectra is degenerate. Numerical analysis to Lorenz dynamical system indicates that the method converges quickly and steadly for arbitrary nonzero initial state.
TWO-DIMENSIONAL PIC-MCC SIMULATION OF ION EXTRACTION
Authors: XIONG JIA-GUI  , WANG DE-WU  ,   清华大学工程物理系，北京  100084
Published: December 2020

To explore more simple and efficient ion extraction methods used in atomic vapor laser isotope separation (AVLIS),two-dimensional(2D) PIC-MCC simulation code is used to simulate and compare several methods: parallel electrode method,Π type electrode method,improved M type electrode method,and radio frequency (RF) reso nance method.The simulations show that,the RF resonance method without magnetic field is the best among others,then the improved M type electrode method.The res ult of simulation of Π type electrode method is quite different from that calcu lated by 2D electron equilibrium model.The RF resonance method with or without m agnetic field has guite different results.Strong resonance occurs in the simulation without magnetic field,whereas no significant resonance occurs under weak magnetic field.And that is quite different from the strong resonance phenomena occurving in the 1D PIC simulation with weak magnetic field.As for practical applications,the RF resonance method without magnetic field has pros and cons, compare d with the M type electrode method.
DIRECT UPCONVERSION SENSITIZATION LUMINESCENCE OF Er:OXYFLUORIDE GLASSCERAMICS
Authors: CHEN XIAO-BO  , LI MEI-XIAN  , N.SAWANOBORI  , ZENG ZHE  , NIE YU-XIN  ,   (1)Sumita Optical Glass,INC.,Saitama,338,Japan; (2)北京师范大学分析测试中心，北京  100875; (3)北京师范大学分析测试中心，北京  100875；中国科学院物理研究所光物理开放研究实验室，北京  100080; (4)中国科学院物理研究所光物理开放研究实验室，北京  100080
Published: December 2020

This paper researches the direct up-conversion sensitization luminescence of ErY b codoped oxyfluoride glassceramics(ErYb:FOV) excited by CW 966nm-diode laser.It is found that the upconversion mechanism of direct upconversion sensitization l uminescence of YbEr:FOV sample is mainly the energy transfer between Er3+ and Yb3+ ion but not the step-by-step absorption of single Er3+ion.This oxyfluoride vitroceramics is forming PbxCd1-x F2 fluoride micro-crystallines.And the rare earth ions tend to concentrate in the micro-crystalline,in which there is an intense cluster effect .So upconversion luminescence is very strong. On the other hand,the log-log vari ation of up-conversion luminescence intensity with laser power emerges a kind of “typical saturation phenomenon”,in which F-P curve is bended gradually result ing from population exhausting in ground state.We also find a new kind of up-con version cooperative radiation fluorescence originating from a kind of Couple Sta te of cluster consisting of two Yb3+ions in this ErYb:FOV.
DOUBLE-CHARGE SOLITONS IN ONE-DIMENSIONAL ARRAY OF MESOSCOPIC JUNCTIONS
Authors: ZHENG XIAO-HONG  , ZENG ZHAO-YANG  , KUANG LE-MAN  ,   湖南师范大学物理系,长沙410081
Published: December 2020

We show that there exist double-charge solitons in a one-dimensional mesoscopic-junction array-in which-there are two excess electrons respectively on two different islands. The prominent feature of a double-charge soliton is its potential peak splitting into double peaks. The two peak values are not equal generally. The dependences of the peak potentials and threshold voltage of a double-charge soliton on the structure parameters of the tunnel junction array are also discussed. We also propose an equivalent single-charge soliton-description for a double-charge soliton.
A FIELD METHOD FOR SOLVING THE EQUATIONS OF MOTION OF A ROTATIONAL REALTIVISTIC BIRKHOFFIAN SYSTEM
Authors: LUO SHAO-KAI  , GUO YONG-XIN  , CHEN XIANG-WEI  , FU JING-LI  ,   (1)辽宁大学物理系,沈阳110036; (2)商丘师范学院数学力学与数学物理研究所,商丘476000; (3)商丘师范学院数学力学与数学物理研究所,商丘476000;长沙大学数学力学与数学物理研究所,长沙410003
Published: December 2020

A field method for solving the equations of motion of a rotational relativistic Birkhoffian system is obtained.An example to illustrate the application of the method is given.
THE SOLITARY WAVE SOLUTIONS TO KdV-BURGERS EQUATION
Authors: Lü KE-PU  , SHI YU-REN  , DUAN WEN-SHAN  , ZHAO JIN-BAO  ,   西北师范大学物理与电子工程学院,兰州730070
Published: December 2020

The study on the hyperbola function method has been done and the application of the method was extended.Furthermore, with the aid of computer algebraic system Mathematica, two kink solitary wave solutions to KdV-Burgers equation were successfully derived.
THE PREFERENTIAL ADSORPTION OF Ge ON Si(111)7×7 SURFACE
Authors: YAN LONG  , ZHANG YONG-PING  , PENG YI-PING  , PANG SHI-JIN  , GAO HONG-JUN  ,   中国科学院物理研究所与凝聚态物理中心北京真空物理实验室,北京100080
Published: December 2020

Ge preferential adsorption on Si(111)7×7 surface at the initial stage has been investigated by ultra-high vacuum scanning tunneling microscopy (UHV-STM). We demonstrate that there is a critical nucleus for the adsorbed Ge clusters on Si(111) 7×7 surface. The center sites of the Ge clusters are located in the areas encircled by three adatoms. Moreover, on the Ge clusters the local density of states near the Fermi level is drastically reduced, compared with that far from the Fermi level.
SPONTANEOUS MAGNETIZATION IN HIGH-Tc SUPERCONDUCTING π RINGS
Authors: DENG PENG  , MENG SHU-CHAO  , WANG FU-REN  , XIE FEI-XIANG  , MA PING  , DAI YUAN-DONG  ,   北京大学人工微结构和介观物理国家重点实验室,物理系,北京100871
Published: December 2020

We analyzed and calculated the spontaneous magnetization in High-Tc superconducting YB2Cu3O7-δ 1-junction and 3-junction rings which contained a π junction. We also deduced the temperature dependence of the spontaneous magnetization in 3-junction π ring. The theoretic results fit the experimental data fairly well.