bluuebunny/crossref_metadata_2025 huggingface dataset:
STABILITY OF THE COHERENT LIGHT INJECTION LOCKING IN SEMICONDUCTOR LASERS,THE RELATED INSTA BILITY PHENOMENA AND THEIR ROUTES TO CHAOS
Authors: GUO CHANG-ZHI  , LIU PENG  ,   北京大学物理系,北京,100871
Published: December 2020

The fundamental equations describing the coherent light injection locking in semiconductor lasers are derived from semi-classical theory, the multi-branch structure and its stability, the steady modulation characteristic and its stability, several kinds of instability phenomena inside and outside the locking region and their distribution in the parametric plane representing the light injection condition are investigated. It is found that the stability region can only exist near the lower boundary and the right side in the locking region of the highest branch, and a self-pulsation region exists near to it. In the central portion in the rest part of the locking region there exists a chaotic region, between self-pulsation and chaotic regions is the transition region. In this transition region and outside the locking region there are bifurcation of self pulsation of 2p type and non-2p type, beat frequency self-modulation, and their mixed forms, the intermitant relaxation oscilation and intermiting chaos, etc., and several new routes to chaos.
EFFECTS OF DISPERSIVE RELATION AND LONGITUDINALLY COUPLED CAVITY (C3) ON THE MODE SPECTRAL BEHAVIOR IN SEMICONDUCTOR LASERS
Authors: GUO CHANG-ZHI  , HUANG YONG-ZHEN  ,   北京大学物理系,北京,100871
Published: December 2020

The effect of the dispersive relation is investigated theoretically and a nominal linewidth broadening enhancement factor αe and an F factor related to the dispersive relation are introduced to modify the spectral linewidth formula of semiconductor lasers. It is found that the spectral linewidth not only can be suppressed by decreasing the linewidth broadening en-hancement factor, but also can be suppressed further by increasing the F factor. The mechanisms of the mode selection and linewidth compression in longitudinally coupled cavity (C3) are analyzed by means of the proposed effective reflectivity method, and the optimum condition for realizing single longitudinal mode with narrow linewidth is noted.
SOLID STATE AMORPHIZATION REACTION IN BINARY ALLOY MULTILAYERS
Authors: YAN ZHI-HUA  , CHEN HONG  , WANG WEN-KUI  ,   中国科学院物理研究所,北京,100080
Published: December 2020

In this paper, we report the amorphization observed in Fe-Ti and Fe-Si systems through a solid state reaction at low temperatures, and confirm the formation of amorphous Ni-Ti alloy after reaction. This new amorphization processes can be considered as the result from competing amorphous phase with crystalline phase in kinetics. A kinetical criterion for forming amorphous phase by solid state reaction is discussed in detail.
EFFECT OF HEAT TREATMENT ON THE MAGNETIC PROPERTIES OF AMORPHOUS Nd4Fe96-xBx ALLOYS
Authors: ZHANG JUN-XIAN  , SHEN BAO-GEN  , YANG LIN-YUAN  , WO FENG  , NING TAI-SHAN  , ZHAO JIAN-GAO  , GUO HUI-QUN  , ZHAN WEN-SHAN  ,   中国科学院物理研究所,北京,100080
Published: December 2020

The effects of heat treatment on the hard magnetic properties and phase components are studied for amorphous Nd4Fe96-xBx alloys prepared by melt quenching technique. The crystallization temperature of amorphous Nd4Fe96-xBx alloys is higher than that of amorphous Fe100-xBx alloys at same B content in the range of 120-190 K. For 15≤x≤25, the samples crystallized from amorphous exhibit the hard magnetic properties, and consist of Nd2Fe14B, Fe3B and α-Fe. It is found that the intrinsic coercivity and magnetic energy product of the samples at optima1 heat treatment show a maximum of 2.8 kOe and 12 MGOe for Nd4Fe77B19 (x=19) alloy annealed at 670℃ for 2 min, respectively. These materials would presumably be used as an inexpensive bonded magnets, due to its higher values of Br and (BH)max.
STUDY OF Ne AUTOIONISING STATES WITH PULSED ELECTRIC FIELD OPTOGALVANIC SPECTROSCOPY
Authors: ZHANG LIAN-FANG  , ZHAO WEN-ZHENG  , SHANG REN-CHENG  , PAN LI  , WANG SHI-LIANG  , WEN KE-LING  , CHEN DIE-YAN  ,   清华大学现代应用物理系,北京,100084
Published: December 2020

35 autoionising energy levels of Ne atom in ns＇(n = l5-35) and nd＇(n = l3-30) series have been determined experimentally with pulsed electric field optogalvanic spectroscopy. The ionization limit of the ns＇ and nd＇ series was found by parametric fitting and the quantum defects of all these levels were calculated. Instead of the direct discharge, pulsed electric field was used in the experiment, to eliminate Stark effects in the optogalvanic spectroscopy.
THEORETICAL CALCULATION OF A NEW METHOD OF MODE-LOCKING FOR LASERS
Authors: ZHU ZHEN-HE  , HUO CHONG-RU  ,   (1)中国科学院物理研究所,北京,100080; (2)中央民族学院物理系,北京,100081
Published: December 2020

A fluctuation model is suggested in this paper for the mode-locked laser incorporating a nonlinear mirror with intensity dependent reflection coefficient. Computer simulation with this model is conducted for varied parameters of Nd: YAG lasers and for two kinds of nonlinear crystal (KTP and KDP). The optimum parameters and conditions under which perfect mode-locking will be achieved are predicted according to the simulation calculation.
INTERACTION OF A INCLUSION WITH A CRACK
Authors: WANG RUI  ,   北京科技大学材料科学与工程系,北京100083
Published: December 2020

The influence on the stress field in the vicinity of a crack tip due to a round inclusion is investigated. The antiplane shear problem is solved. After the classical stress field and stress strenth factor are obtained, the nonsingular nonlocal stresses in the vicinity of crack tip is obtained. The application of the solution is discussed.
THE GROWTH DYNAMICS OF Si(111) MBE STUDIED BY RHEED INTENSITY OSCILLATIONS
Authors: CHEN KE-MING  , JIN GAO-LONG  , SHENG CHI  , YU MING-REN  ,   (1)复旦大学表面物理实验室,上海,200433; (2)复旦大学表面物理实验室,上海,200433,中国科学院半导体研究所
Published: December 2020

The growth dynamical processes of Si(111) molecular beam epitaxy under different growth temperature are studied by RHEED intensity oscillations. The Si(lll) epilayer grew in a "step flow" mode at the temperature above 520℃(growth rate 0.02 nm/s), and in a "2D nucleation" bilayer mode at temperature range between 520℃ and 420℃. Below 380℃, even at room temperature, the growth is still in a bilayer mode. The RHEED intensity oscillation shows a monoatomic layer mode during the initial stage of growth, which is believed due to the superposition of two kinds of oscillations originated from coherent elastically scattering and incoherent scattetring or surface diffuse scattering.
PREPARATION OF DIAMOND FILMS BY DC ARC DISCHARGE AND IN SITU MEASUREMENTS OF THE PLASMA BY OPTICAL EMISSION SPECTRA
Authors: ZHANG FANG-QING  , ZHANG YA-FEI  , YANG YING-HU  , LI JING-QI  , CHEN GUANG-HUA  , JIANG XIANG-LIU  ,   (1)北京市科学技术研究院,北京,100044; (2)兰州大学物理系,兰州,730001
Published: December 2020

High quality diamond films have been rapidly synthesised by the DC arc discharge plasma CVD in a hydrogen-methane mixture gas. The properties of the films are tested and analyzed by scanning electron microscopy, X-ray diffraction and Raman spectra. In order to find out the growth mechanism of vapor deposited diamond, in situ optical emission spectra of plasma under practical growth conditions are measured. It is found that the key factor of rapid growth diamond film is the presence of a large number of atomic hydrogen in the plasma.
STRONG-FIELD AUTOIONIZATION BY SQUARE LASER PULSES
Authors: CHEN RONG-QING  , XU ZHI-ZHAN  , SUN LAN  , YAO GUAN-HUA  , ZHANG WEN-QI  , LI PING  ,   中国科学院上海光学精密机械研究所,上海,201800
Published: December 2020

Previous studies on strong-field autoionization involving high-order ionization processes are mainly investigated for the cases of CW laser irradiations. This paper extends those studies to the cases of square laser pulses with arbitrary widths. Populations of the ground state and the line shapes of the autoionizing resonance are discussed. It is shown that strong-field autoionization and the high-order ionization processes are drastically affected not only by the intensities but also by the time of interaction between atoms and laser field.
SU(2) SQUEEZING IN TWO-LEVEL ATOMIC MIXED-STATE
Authors: LIU SHI-BING  , HUANG CHANG-CHUN  , LI HONG  ,   江西师范大学物理系,南昌,330027
Published: December 2020

In this paper, the behavior of SU(2) squeezing of the mixed-state in two-level atom are studied by means of the time-evolution operator method. We have obtained new results that the mixed-state atomic squeezing under interacting of the light field is deeper than the general pure-state atomic SU(2) squeezing. Furthermore, the squeezing value of the atom in pseudo-ground state is more greater than that in pseudo-excited state. The relation between the statistical probability of atomic level population and the squeezing is studied by numerical calculations.
ANALYTICAL STUDY ON THE RESONANT ABSORPTION OF LIGHT IN NON-UNIFORM PLASMA
Authors: SHENG ZHENG-MING  , MA JING-XIU  , XU ZHI-ZHAN  ,   中国科学院上海光学精密机械研究所,上海,201800
Published: December 2020

The resonant absorption of light in cold plasma for linear density profile has been calculated analytically both for long and short scalelengths by calculating the reflectivity from the plasma and vaccum interface. The results in long scalelength case are in agreement with the well-known results but with a higher order in accuracy, and that in short scalelength case are consistent with numerical calculation.
NONLINEAR COUPLING OF THE ELECTROSTATIC DRIFT WAVE AND SHEAR ALFVEN WAVE IN MAGNETIZED PLASMAS
Authors: CHEN YIN-HUA  , ZHU DONG-PEI  , YANG WEI-HONG  ,   中国科学技术大学近代物理系,合肥,230026
Published: December 2020

In terms of Hasegawa-Wakatani equations,the nonlinear coupling of the electrostatic drift wave and the shear Alfven wave in magnetized plasmas has been investigated. The dipolar vortex solutions of the nonlinear equation system are obtained. These solutions belong to the intrinsic electromagnetic vortices, the corresponding magnetic field perturbations and the longitudinal current are continuous on the boundary of the vortex.
STIMULATED RAMAN SCATTERING IN LASER PLASMA TARGETS
Authors: ZHANG JIA-TAI  , XU LIN-BAO  , CHANG TIE-QIANG  , ZHANG SHO-GUI  , NIE XIAO-BO  , WANG SHI-HONG  , WANG WEI-XING  ,   北京应用物理与计算数学研究所,北京,100088
Published: December 2020

In this paper, an one and a half dimensional (1(1/2)-D, one space dimensionand two velocity dimension) plasma cloud-in-cell simulation code (CIC) has beendeveloped. It is used to study SRS in laser-plasma targets from the Shenguang-12# Nd-glass laser facility (λ=1.053μm,τ= 850ps IL= 3×1014—3×1015W/cm2). The results on the linear growth rates of the scattering electromagnetic waves and Lan-gmuir waves and nonlinear saturation are obtained in detail. Other results such as the time development of the electron distribution function and temperature and fraction of hot electron are also presented. In addition,temperature of thermal electron (1.4-2.5keV) in the underdense coronal plasma region is determined by spectrum analysis of SRS light, as well as contour figure for density distribution and averagedensity (0.12-0.14nc, n=1/4nc). These results agree with experiments.
GYROKINETIC EQUATION APPLICABLE TO RADIOFREQUENCY HEATING
Authors: CHEN YAN-PING  , CAI SHI-DONG  ,   中国科学院物理研究所,北京,100080
Published: December 2020

The linear gyrokinetic equation near gyrofrequency in the presentation of three independent electric field components is derived by following the method of Chen and Tsai. This equation is suitable for investigation of radiofrequency heating in the inhomogeneous plasmas-The solutions of the equation for axisymmetric tokamaks is given.
COMPARISON BETWEEN THE ELECTRONIC STRUCTURES OF Si(lll) 31/2×31/2-Sn AND-Al
Authors: FU HUA-XIANG  , YE LING  ,   复旦大学物理系,上海,200433
Published: December 2020

By investigating orbital overlap population (OOP) resulting from the interaction between adatom and substrate Si atom, and total density of states of the cluster, it is found that Si(lll) 31/2×31/2- Sn has a half filled surface band which makesthe surface metallic. But for Si(lll) 31/2×31/2-Al, its bonding surface states are occupied fully with electrons and the antibonding surface states are empty, which makes the surface appear to be semiconducting. These calculation results are consistent with the experimental ones. A clear description on the interactions between Al, Sn and surface Si atom is also presented in this paper.
PERTURBATION-ITERATION APPROACH TO ATOMIC PROCESSES IN STRONG LIGHT FIELDS
Authors: CHEN BAO-ZHEN  ,   北京师范大学低能核物理研究所,北京,100875
Published: December 2020

Starting from the space-translated version of Schr?dinger equation of H-atoms in the laser fields with circular polarization, the features of the dressed coulomb potential are analyzed, a small expansion parameter is found and a perturbation-iteration method is presented. Then the zero to second order approximation equations of Floquet-Schr?dinger equation are derived It is shown that the above-mentioned expansion in the small parameter makes the iteration method to give a correct result. Furthermore, the advantages of the approach are qualitatively displayed by a brief comparison of the results given in this paper with the previous results.
GENERATION OF SQUEEZED STATE LIGHT FROM LASERS VIA NON-DEGENERATE BACKWARD FOUR WAVE MIXING IN LASER CAVITIES
Authors: LIU SHANG-QING  , XIA YU-XING  ,   中国科学院安徽光学精密机械研究所,合肥,230031
Published: December 2020

A scheme is suggested in this paper, by which squeezed state light can be radiated from lasers directly via non-degenerate backward four wave mixing in laser cavities. Full quantum theory calculations predict that the output light shows good squeezing.
STUDY ON Sb-DOPED Bi SYSTEM SUPERCONDUCTOR
Authors: BAI PEI-GUANG  , LIU JIAN  ,   内蒙古大学物理系,呼和浩特,010021
Published: December 2020

In the samples of Sb proper doping Bi-Sr-Ca-Cu-O system, the content of the high temperature phase (110K phase) is obviously much higher than that of the Sb-free samples'. Sb has a function of accelerating the formation of the high Tc phase. For the nominal composition of Bi2-xSbxSr2Ca2.5Cu3.7Oy x = 0.1 is most beneficial to the formation of the high Tc phase, After quenching in liquid nitrogen and annealing at low teperatures, it is found that the low Tc phase (80K phase) is firstly formed when the samples are sintered at 865℃, then the low Tc phase changes to the high Tc phase, until all materials become the high Tc phase eventually. The value of Tc increases continuously with time lasting. If annealed at lower em-perature, the high Tc phase will change to the low Tc phase. Based on this discovering, after sintering at high temperature, for a long time, fast cooling to a low temperature, annealing for some time, then naturally cooling to room temperature, we have successfully prepared the high Tc single phase superconductor with zero resistance temperature 113K.
ARUPS INVESTIGATION OF CO COADSORPTION WITH K ON W(100) SURFACE
Authors: BAO SHI-NINO  , ZHU LI  , XU YA-BO  ,   浙江大学物理系,杭州,310027
Published: December 2020

Hel ultraviolet photoemission studies of CO coadsorption with different K coverages on W (100) surface show that the 1π/5σ level of α-CO shifts from 8.6eV to 9.3eV relative to the Fermi level while the K coverages increase, this indicates the increase of electron backdonation into 2π* of α-CO. Two independent peaks are found around 5.5 eV (Characteristic of β-Co), one is at 5.2eV, another is at 6.0eV. The peak at 5.2eV grows with increasing K coverages, its energy position is the same as that of O coadsorption with K on W(100) surface, this suggests that K forms bond to O of β-CO.
THE l-MIXING CROSS SECTION OF RYDBERG STATES OF ATOMIC Rb AND THE SCALING LAW
Authors: LIU HONG  , CHEN AI-QIU  , LI BAI-WEN  ,   中国科学院武汉物理研究所波谱与原子分子物理开放研究实验室,武汉,430071
Published: December 2020

On the basis of impulse approximate merhod, a kind of analytical wavefunctions based on a potential model was used to calculate the l mixing cross section of thermal collision of Ryd-berg states of atomic Rb with rare gas (He, Ne). The results were compared with the experimental results and other theoretical values. These results show that there exists a kind of scaling law for the l mixing cross section of Rydberg alkali atoms.
AMPLITUDES OF ELECTRONIC WAVEFUNCTIONS AT NUCLEI FOR ATOMS (I)——HIGH ENERGY PHOTOIONIZATION PROCESSES OF ATOMIC IONS
Authors: LIU LEI  , LI JIA-MING  ,   中国科学院物理研究所,北京,100080
Published: December 2020

Based on the atomic self-consistent-field theory, we have performed relativistic calculations for reduced normalization factors and photoionization cross sections of occupied shells of various ionized iron and uranium atoms. For photoionization cross sections of a specific subshell of an atom with various degrees ionization, their ratios at photon energies above about 101keV agree with the squares of the ratios of the corresponding reduced normalization factors within 1%.
THE ELASTIC PROPERTIES OF COBALT OXIDE IN MAGNETIC PHASE TRANSITION
Authors: WAGN JI-FANG  , WANG RU-JU  , M. H. MANGHNANI  , XIONG DA-HE  ,   (1)Hawaii Institute of Geophysics,University of Hawaii,USA; (2)中国科学院地质研究所,北京,100029; (3)中国科学院物理研究所,北京,100080
Published: December 2020

Using ultrasonic phase comparison method, the elastic properties and pressure derivatives of paramagnetic and antiferromagnetic phase of cobalt oxide are measured. The characteristic of interatomic forces in these two phases, the nature of bulk modulus and compressibility at Néel temperature, and the order of phase transition of cobalt oxide are discussed based on the experimental results.
MAGNETIC PROPERTIES OF AMORPHOUS Co70Cr20Zr10 ALLOYS NEAR THE CURIE TEMPERATURE
Authors: HU FENG-XIA  , SHEN BAO-GEN  , CHEN JIN-CHANG  , GUO HUI-QUN  ,   (1)北京师范学院物理系,北京,100037; (2)中国科学院物理研究所磁学开放研究实验室,北京,100080
Published: December 2020

Magnetic properties of the amorphous Co70Cr20Zr10 alloys near the Curie temperature are reported. The behavior is found to obey second-order phase transition laws with critical indices: β=0.45 ± 0.02, γ= 1.9 ±0.1, δ = 5.13±0.05, and the ferromagnetic Curie temperature Tc= (186.7±0.2)K. The critical indices satisfy the scaling law relationship γ = β(δ- 1), but their values deviated with the 3D-Heisenberg model. This behavior may arise from the magnetically inhomogeneous behavior of the alloy. Finally, the temperature dependence of the Kouvel-Fisher exponent γ(T) is discussed.
TEMPORAL ASPECTS OF ABSORPTIVE TWO-PHOTON OPTICAL BISTABILITY
Authors: WANG YING-HAI  , HU CHENG-SHENG  , WANG ZHI-CHENG  ,   兰州大学物理系,兰州730001
Published: December 2020

We investigate the temporal aspects of absorptive two-photon optical bistability described by a semiclassical theory in the limit of a fully developed hysteresis cycle and when all decay rates have comparable magnitude. We show by multiple time-scale perturbation analysis that near the high-transmission branch the behavior of the system is governed by an equation for the field amplitude which determines the long-time evolution of the system, whereas, near the low-transmission branch all dynamical variables vary on the long time scale, and it is possible to describe the transition between the two stable branch by simple equations.
CAVITON FORMATION AND SECOND HARMONIC EMISSION DURING THE INTERACTION OF MICROWAVE WITH INHOMOGENEOUS PLASMA
Authors: LIU JIAN-MIN  , JIANG YONG  , DING WEI-XING  , HU GEN-ZE  , YU CHANG-XUAN  ,   中国科学技术大学近代物理系,合肥230026
Published: December 2020

The experimental simulations of laser-plasma interaction process by means of the microwave-plasma interaction have been performed in a steady state plasma device. The evolution of cavitom in the nonlinear interaction is experimentally investigated. The good agreement between experimental results and numerical calculation of Zakharov equation is obtained. The second harmonic emission spectrum is measured, and the mechanism of red-shift of second harmonic frequency is discussed.
WHIRLPOOL STRUCTURE IN THE PROCESSES OF MICROCRYSTAL GROWTH BY CVD METHODS
Authors: WANG YOU-WEN  , XU YU-QIN  , DING ZI-SHANG  , YAO HONG-NIAN  ,   (1)浙江大学材料系,杭州310027; (2)浙江大学分析测试中心,杭州310027
Published: December 2020

The whirlpool structure have been observted in HREM investigation of Si : H films deposited by glow discharge and SiC ultrafine powder synthesized by thermal chemical vapor reaction method. In this structure, strong planes are arranged around its nuclei and this seems to be whirlpools in HREM image. In this article, the cheracters of whirlpool structure are described, its forming reason and the condition under which it can be retained are analysed, and the dependence of it on microcrystal nucleation and growth processes are discussed.
STUDY ON WETTING TRANSITION IN A FLUID MIXTURE——CRITICAL EXPONENTS IN THE WETTING TRANSITION
Authors: Song Yan  , Ding E-Jiang  , Huang Zu-qia  ,   (1)北京师范大学低能核物理研究所,北京100875; (2)中国科学院理论物理研究所,北京100080; (3)中国科学院理论物理研究所,北京100080;北京师范大学低能核物理研究所,北京100875
Published: December 2020

The expression of critical exponents in wetting transition at two-phase and three-phase coex-istence in Sullivan mixture are studied, It is found that the critical exponents depend neither on the model parameters not on the symmetry of dynamical potential, i. e.: the exponents have universality.
BACKWARD SCATTERING AND OPTICAL DIODE EFFECT IN Mn DOPED KNSBN CRYSTAL
Authors: SHE WEI-LONG  , WU QI  , LI QING-XING  , YU ZHEN-XIN  , ZHANG QING-LUN  , CHEN HUAN-CHU  ,   (1)山东大学晶体材料研究所,济南250100; (2)中山大学激光与光谱学研究所,广州510275
Published: December 2020

When a He-Ne laser beam (632.8 nm) with the power of milliwatts or submilliwatts penetrates through a Mn doped KNSBN crystal, a phenomenon of strong backward scattering is observed. At the same time, an optical diode effect which is associated with the backward scatering is also observed. In a certain range, the response time constant T of the optical diode effect is inversely propotional to the incident intensity on the surface of the crystal. The τ is decreased by one order of magnititude when a K9 glass plate which serves as a feedback mirror is introduced. A time constant of 1.5s and a ratio of the forward transmissivty to the backward one, which is greater than 15.3, have been obtained. A theoretical explanation is given on the basis of the experimental results
EFFECT OF SURFACE LOCAL ENRICHMENT ON PREFEREN-TIAL SPUTTERIONG OF ALLOY
Authors: WANG ZHEN-XIA  , PAN JI-SHENG  , ZHANG JI-PING  , TAO ZHEN-LAN  ,   中国科学院上海原子核研究所,上海201800
Published: December 2020

The angular distributions of atoms sputtered from Ni-50Wt%Ti, Fe-30Wt%W and Ag-50Wt%Cu alloys by 27keV Ar+ ions bombardment nave been masured. It has been found that Ti, Fe and Ag atoms were sputtered preferentially at small angles. The sputtered surfaces have been analyzed by SEM combined with EPMA. It has been showed that all the surface topographies of three samples consisted of two different parts i.e. convex and concave regions, corr responding dif ferent components being richer at different region. A model has been suggested to explan this phenomenon.
PROPERTIES AND MICROSTRUCTURES OF MELT PROCES-SED (YHo)Ba2Cu3O7-y SUPERCONDUCTOR
Authors: FENG YONG  , ZHOU LIAN  ,   西北有色金属研究院,宝鸡721014
Published: December 2020

We have prepared (YHo) Ba2Cu3O7-y superconductors with hige Jc value by powder melting process (PMP) method. The DTA result shows that the melting temperature of Y-system superconductor can be reduced by Ho addition. The Jc value can be improved and the size of 211 phase can be reduced by Ho substitution. Microstructures and X-ray diffraction pattern indicate that the 123 grains are preferentaially aligned with mutually parallel a-b conductive planes. There are a number of twins and fine 211 particles in the sample. It is also found that many crystal defects exist around the 211 phase. These defects may act as pinning centers.
SURFACE GEOMETRY OF TWO SCHWARZSCHILD BLACK HOLES
Authors: QIANG WEN-CHAO  ,   西安冶金建筑学院基础课部,西安710055
Published: December 2020

The Gaussian curverture, equatorial and polar circumferences are calculated for the event horizons of two Schwarzschild black holes. Their variations following the change of the distance of two black holes are also examined. The results show that the geometrical property of the horizon of one black hole is affected by the other.
SELFCONSISTENT STUDY OF DEUTERON-NUCLEUS MICROSCOPIC OPTICAL POTENTIALS
Authors: SHI JIAN-QING  ,   浙江省技术物理应用研究所,杭州310012
Published: December 2020

The analytical formula for deuteron-nucleus microscopic optical potentials is derived using the mass operator method of Green function, and the nucleon density distributions of target nuclei are determined with the semiclassical variation (SCV) approach. These formula and density distributions are utilized ro evaluate the real and imaginary parts of 2D+40Ca,2D+60Zr and 2D+208Pb optical potentials at different energies. The potentials obtained in this way are fully selfconsistent and microscopic, since the same Skyrme interaction is employed in determining the nucleon density distributions of target nuclei and in clacula-ting the potentials.
NEW τ PHASES IN Al65Cu20Co15 ALLOY
Authors: MENG XIANG-MIN  , HU KUI-YI  , WU YU-KUN  , HUANG JIN-XIU  , CUI SHENG-LAN  ,   (1)化学工业部感光材料技术开发中心基础部,沈阳110021; (2)中国科学院金属研究所固体原子象实验室,快凝非平衡合金实验室,沈阳110015
Published: December 2020

By using electron diffraction method, three new vacancy ordered phases, τ23,τ27 and τ35, have been found in the conventionally solidified Al65Cu20Co15 alloy. They do not belong to the known Fibonacci series The computed kinematical intensities shown that the stacking sequences of τ23,τ27 and τ35 are respectively 332323232, 3323323323 and 3323323323323.
DEGENERACIES OF THE ELECTRONIC AND PHONON STATES OF THE TWO-DIMENSIONAL QUASICRYSTALS WITH N-FOLD ROTATIONAL SYMMETRY
Authors: HUANG XIU-QING  , LIU YOU-YAN  , DENG WEN-JI  ,   (1)华南理工大学应用物理系,广州510641; (2)中山大学物理系,1992级博士研究生广州510275
Published: December 2020

The similarity transformation is introduced which reduce the hamiltonian and the dynamical matrix of the two-dimensional quasicrystals with A/-fold rotational symmetry. For the degeneracy, when N is even number, N-2 out of N+2 of electronic and phonon states are doubly degenerate and 4 out of N+ 2 are non-degenerate, and as N is odd number, N-1 out of N+1 of electronic and phonon states are doubly degenerate and 2 out of N+1 are nondegene-rate. We use group theory +o study the degeneracies of twodimensional quasicrystals and obtain the same conclusion.
HIDDEN LOCAL GAUGE INVARIANCE IN FATEEV-ZAMOLO-DCHIKOV QUANTUM SPIN CHAIN UNDER OPEN BOUNDARY CONDITIONS
Authors: XIONG ZHUANG  , GUAN XI-WEN  , ZHOU HUAN-QIANG  ,   四川师范大学物理系,成都610066
Published: December 2020

Hidden local gauge invariance in Fatteev-Zamolodchikov quantum spin chain under open bondary conditions is studied in the framework of quantum inverse scattering method (QISM). Our results show that the Hamiltonian and its eigenvectors are explicitly gauge-dependent while the energy eigenvalues and the Bethe equations are gauge-invariant.
GROWTH OF INTERFACE WITH AN EXTERNAL FIELD
Authors: HAN FEI  , MA BEN-KUN  ,   北京师范大学物理系,北京100875
Published: December 2020

The dynamics of a growing interface with an external field is investigated. The nontrivial fixed point is found and the exponents are calculated. The result shows that the external field tends to smoothen the interface and does not break the Galilean invariance.
QUANTUM TREATMENT OF OPTICAL SOLITON PROPAGATION
Authors: WEN YANG-JING  , FENG YU  , FU CHUAN-HONG  ,   江西师范大学物理系,南昌330027
Published: December 2020

In this paper, we treat optical soliton propagation with quantum method. We derive the quantum nonlinear Schrodinger equation (QNSE) with corrections by using the micro model of a Kerr-like medium and dispersion relation. We also find the perturbation solution of thisequation and study the influence of corrections on squeezing. The result indicates that thethird-order dispersion has no influence on squeezing and the term in ?/(?τ)(φ+φ2) makes theamount of squeezing decrease.
OBSERVATION OF NEGATIVE CRYSTALS IN LITHIUM TRIBORATE SINGLE CRYSTALS
Authors: TANG DING-YUAN  , LIN XIANG  , ZHAO QING-LAN  , ZENG WEN-RONG  , TAN QI-GUANG  , MAO HONG-WEI  , ZHONG WEI-ZHUO  , HUA SU-KUN  ,   (1)中国科学院福建物质结构研究所,福州350002; (2)中国科学院上海硅酸盐研究所,上海201800
Published: December 2020

A novel type of inclusion—negative crystal in lithium triborate (LBO) crystals,whichis an important new nonlinear optical material,has been observed and investigated by optical microscope,X-ray topography and light scattering topograph. Theirs compositions and nature are made clear and the growth mechanism are also discussed.
MOMBE GROWTH OF CARBON DOPED p-TYPE GaAs AND InGaAs
Authors: QI MING  , J. SHIRAKASHI  , E. TOKUMITSU  , S. NOZAKI  , M. KONAGAI  , K. TAKAHASHI  , LUO JIN-SHENG  ,   (1)东京工业大学电气电子工学科,东京152,日本; (2)东京工业大学电子物理工学科,东京152,日本; (3)东京工业大学电子物理工学科,东京152,日本;西安交通大学电子工程系西安710049; (4)西安交通大学电子工程系,西安710049
Published: December 2020

The growth and electrical properties of carbon doped p-type GaAs and InGaAs grown by metal-organic molecular beam epitaxy (MOMBE) using trimethylgallium (TMG), solid arsenic and solid indium as source materials have been studied systematically. The experimental results show that the growth rate and hole concentration of the samples are affected strongly by growth temperature and molecular beam fluxes,especially for InGaAs epilayers. The mechanism of carbon incorporation and its influence on the properties of the samples were also analysed based on the experimental results. It is shown that the changes in growth rate and hole concentration are mainly due to the dependence of TMG decomposition process on the growth condition.
CHARACTERISTICS OF NONLINEAR MAGNETOSTATIC SURFACE WAVES
Authors: WANG QI  , BAO JIA-SHAN  , CAI YING-SHI  , A. D. BOARDMAN  ,   (1)上海科学技术大学物理系,上海20l800; (2)索福特大学物理系,索福特MS4WT,UK
Published: December 2020

The dynamic nonlinear magnetization of different order induced by microwaves in a ferromagnetic material is derived by using perturbation theory. The characteristics of the nonlinear magnetostatic surface wave with wavevector k, making an arbitrary angle to the bias magnetic field, is analysed rigorously. We conclude that the envelope magnetostatic surface solitons in ferromagnetic films can not be generated in all possible direction of propagation.
A STUDY OF RAMAN SPECTRA AND SOFT MODE BEHAVIOR IN NANOCRYSTALLINE MATERIALS Pb1-xBaxTiO3
Authors: MENG JIN-FANG  , ZOU GUANG-TIAN  , CUI QI-LIANG  , LI XI  , TANG JIAN-XIN  , ZHAO MU-YU  ,   (1)吉林大学超硬材料国家重点实验室,长春130023; (2)吉林大学化学系,长春130023
Published: December 2020

The Raman spectra of Pb1-xBaxTiO3(x=0,0. 2,0. 3) have been measured. Experimental results show that there is an obvious effect of small size of crystal in the system.
A STUDY OF THE CHEMISORPTION OF CH3NO2 ON Cu(lll) SURFACE
Authors: DU ZHI-QIANG  , ZHANG XUN-SHENG  ,   (1)浙江大学化学系,杭州310027; (2)浙江大学物理系,杭州310027
Published: December 2020

The chemisorption of CH3NO2 on Cu(111) surface has been studied by the semiempirical quantum mechanical method (CNDO/2) of cluster models. The results indicate that the bridge site of Cu(111) is preferable for CH3NO2 adsorption, the orientation of CH3NO2 adsorption is that -NO2 points downward to the Cu surface, and the angle between the plane ONO and Cu-Cu bond is 60o. The orientation of adsorption and the density of states calculated by CNDO/2 calculation are in agreement with the experimental results. The analyses of atomic orbital percentages show that CH3NO2 adsorption is the result of interaction of 2p atomic orbitals of 0 for CH3NO2 with 3d atomic orbitals of Cu.
STUDIES OF THE REAL-TIME OPTICAL CORRELATION STORAGE IN LiNbO3:Fe Photorefractive Crystals
Authors: LU YI  , LIU SI-MIN  , SHU HUA-DE  , SUN QIAN  , ZHANG GUANG-YIN  , XU JING-JUN  , LIU JUN-MIN  ,   (1)南开大学物理系; (2)天津理工学院二分院
Published: December 2020

The real-time optical correlation-storage in photorefractive crystals has firstly been realized. It possesses the advantages of both storage and correlator, as well as the real-time character of photorefractive devices. It can performa real-time and fast selection of imformation correlated to the input ones from a great amount of stored imformation. The correlation degree of every information with the input ones and its coding number are immediately obtained from the intensity and position of the correlation points. This principle is based on the selectivity of photorefractive matched filter. Hence this device has wide prospect of application.
COLLISION STRENGTHS AND RATE COEFFICIENTS OF Li-LIKE IONS BY ELECTRON IMPACT
Authors: FANG QUAN-YU  , CAI WEI  , SHEN ZHI-JUN  , ZOU YU  , LI PING  , XU YUAN-GUANG  ,   北京应用物理与计算数学研究所
Published: December 2020

The collision strengths of excitation by electron impact from nl to n′l′ with n(n′)≤7 of Li-like ions are computed systematically. The results agree with available data within 10%. The collision strengths are scaled and fitted with a least-squre spline method. As a result, the collision strengths and thermally averaged rate coefficients in the entire range can be determined by ten parameters for one transition process.
TEMPERATURE DEPENDENCE OF PERMEABILITY FOR Fe-Cu-Nb-Si-B ALLOY
Authors: WANG ZHI  , HE KAI-YUAN  , YIN JUN  , ZHAO YU-HUA  ,   (1)东北大学材料科学与工程系; (2)东北大学材料科学与工程系;天津理工学院
Published: December 2020

The correlation between initial permeability μi and temperature T(μi-T curve) for the Fe73.5Cu1Nb3Si13.5B9 alloy annealed at 300—610℃ was investigated.Three types of μi-T curve were observed. The corresponding annealing temperatures are (1)Ta≤460℃,(2) 480℃≤Ta≤580℃,(3) 590℃≤Ta≤610℃.The phase structures of the alloy corresponding to the three types of μi-T curve were analysed and the mechanisms for the changes of μi with T were also discussed.
THE OPTICAL PROPERTIES OF STRAINED SUPERLATTICE (ZnS)1/(ZnSe)1(001)
Authors: LI KAI-HANG  , HUANG MEI-CHUN  ,   厦门大学物理系
Published: December 2020

The linear muffin tin orbitals method was adopted to calculate the band structures of the strained- superlattice (ZnS)1/(ZnSe)1(001) grown on the Si substrate.In our calculation the external adjusted potential was used to overcome the problem of too small a band gap in it.On the basis of relatively accurately calculated band structure and wave function for this system,we calculated the imaginary part of dieletric function of the superlattice system.The results showed that the optical properties of (ZnS)1/(ZnSe)1(001) grown on the Si substrate consisted of the optical properties of bulk ZnS and of bulk ZnSe,and they have rather good optical response over a wide range of photon energy;futhermore,the superlattices are direct band gap materials.Thus the superlattices will become the promising materials for optoelectronic device applications.
CALCULATION OF FRANCK CONDON FACTORS FOR- THE TWO BAND SYSTEMS A1Π→X1Σ+ AND b3Σ+→a3Π OF BF
Authors: ZHANG ZHONG-MING  , XIONG YE  ,   云南大学物理系
Published: December 2020

From the nuclear Schrdinger equation of a diatomic molecule with the vibration rotational interaction term,we derive a wave function which is related not only with vibrational quantum number,but also with rotational one.The Franck Condon factors of the two band systems A1Π→X1Σ+ and b3Σ+→a3Π of BF are calculated by use of the derived wave function with the rotational quantum number ranging from J=0 to J=200.The results obtained can be used in the cases under low or high temperature condition,and also that under the condition of strong shock wave.
PHOTOLUMINESCENCE OF Er IN SiOx
Authors: WAN JUN  , SHENG CHI  , LU FANG  , GONG DA-WEI  , FAN YONG-LIANG  , LIN FENG  , WANG XUN  ,   复旦大学应用表面物理国家重点实验室，上海  200433
Published: December 2020

Erbium-doped SiOx is prepared by molecular beam epitaxy. The influence of Er on the incorporation of O is studied by using Auger specstrocopy. Photoluminescence(PL) peaks around the wavelength of 1.53μm have been observed within the temperature range of 18 to 300 K after annealing. The relationship between PL intensity and annealing temperature is discussed. The temperature dependence of the PL intensity shows an exponential decay with an activation energy of 12 meV at low temperatures (＜100 K) and 150 meV at high temperatures (＞100K).
XPS STUDIES OF CeO2/Nb2O5 INTERFACE EFFECT ON THE IMPROVEMENT OF THE OXYGEN SENSITIVITY OF CeO2 LAYER
Authors: DU XIN-HUA  , LIU ZHEN-XIANG  , XIE KAN  , WANG YAN-BIN  , CHU WU-YANG  ,   (1)北京科技大学材料物理系，北京  100083; (2)中国科学院物理研究所表面物理国家重点实验室，北京  100080
Published: December 2020

The CeO2 single layer and CeO2/Nb2O5 double-layer films have been deposited on a Al2O3 ceramic substrates by a reactive rf/dc sputtering magnetron system. The variation of kinetic behavior of oxygen in CeO2 single layer with temperatures, and also the influence of CeO2/Nb2O5 interface on oxygen sensitivity of the films have been studied by XPS. X-ray photoelectron spectra of Ce3d core level were deconvoluted by Gaussian function for calculating the different concentration of Ce3+ and Ce4+ in the films. The results have shown that the CeO2/Nb2O5 double-layer could improve reduction capability of Ce4+ easily due to the interface effect, so that the reduction capability is higher in CeO2/Nb2O5 double-layer than they were in CeO2 single layer.
ETCHING PROPERTIES OF AMORPHOUS HYDROGENATED CARBON FILMS IN A MULTIPOLE ELECTRON CYCLOTRON RESONANCE OXYGEN PLASMA SYSTEM
Authors: NING ZHAO-YUAN  , CHENG SHAN-HUA  ,   苏州大学物理科学与技术学院，苏州  215006
Published: December 2020

The etching properties of amorphous hydrogenated carbon films deposited from benzene vapor in a multipole electron cyclotron resonance (ECR) plasma-enhanced chemical vapor deposition system have been investigated.Etch rates of these carbon films as a function of the process variables,includ-ing gas pressure and microwave power were measured,and compared with other resist materials.The results show that the film has high etching resistance against oxygen,and etch rate of the film not only closely correlated with etching process parameters,but also with the deposition conditions.This film could be used as a resist in dry etching process.
A GENERAL APPROACH TO THE BOSE-EINSTEIN CONDENSATION OF NEUTRAL ATOMS WITH REPELLENT INTERACTION
Authors: TAN WEI-HAN  , YAN KE-ZHU  ,   上海大学物理系，上海  201800
Published: December 2020

In this paper a general approach to the Bose-Einstein condensation of neutral atoms with repellent interaction is presented.Especially in the case of free atoms (V=0) with repellent interaction,an exact solution for the atom's wave function can be derived,and therefore the calculation of atom's Bose-Einstein condensation is completed.
THE ELECTROMAGNETIC FIELD TENSOR FOR THE SOURCE OF FIELD POSSESSING BOTH ELECTRIC AND MAGNETIC CHARGES IN GENERAL RELATIVITY
Authors: ZHANG JING-YI  ,   湛江师范学院物理系，湛江  524048
Published: December 2020

A method of obtaining electromagnetic field tensor for the source of the field possessing both electric and magnetic charges is given. As an example, in Kerr-Newman space-time with a large number of magnetic charges the method is used, and the results are the same as those obtained by making electric charge a complex extension directly to e+iq.
ab initio CALCULATION OF THE POTENTIAL ENERGY FUNCTION AND THERMODYNAMIC FUNCTIONS FOR GROUND STATE X5Σ- OF PuO
Authors: GAO TAO  , WANG HONG-YAN  , YI YOU-GEN  , TAN MING-LIANG  , ZHU ZHENG-HE  , SUN YING  , WANG XIAO-LIN  , FU YI-BEI  ,   (1)四川大学原子分子物理研究所，成都  610065; (2)西南核物理与化学研究所，绵阳  621900
Published: December 2020

The potential energy function for ground state X5Σ- of the PuO molecule was worked out by the quadratic configuration interaction of single and double substitution method, based on the approximation of relativistic effective core potential for Pu atom and all-electron 6-311G* basis set for O atom. The calculated results for Re,De,Be,αe,ωe and ωeχe are 0.183nm,7.3909eV,0.3365,0.001642,781.15,and 2.77cm-1,respectively.In addition,the thermodynamic functions ΔH0,ΔS0，ΔG0 and Cp of the PuO(g) in standard state are also calculated,which are -118.88kJ/mol，96.16J/mol·K，-147.55kJ/mol,and 31.5656J/mol·K,respectively. All these results are in good agreement with the experimental data.
A TWO-STREAM GYROTRON TRAVELLING WAVE AMPLIFIER
Authors: YANG YUN-YUAN  , DING  WU  ,   (1)北京应用物理与计算数学研究所，北京  100088; (2)中国工程物理研究院北京研究生部，北京  100088
Published: December 2020

A new idea of using two electron beams to widen the bandwidth of a Gyro-TWA is put forward.Theoretical and numerical investigations show that:the new model can produce wideband and high-power output,and its gain is much higher compared with the existing wideband model.When the current of the two beams is 10A,their voltage are,respectively,90 and 153kV,the velocity ratio are 1.0 and 0.62,and their axial momentum spreads are 5.5% and 1.2%,the output saturated bandwidth can reach at least 22%,the peak power,efficiency and gain are 395kW,16% and 62dB,respectively.If we taper the axial guiding magnetic field at the end of the interaction region,a constant bandwidth of 23% can be achieved with the peak output power 280kW.
Properties of Magnetostatic Wave Propagating in YIG Waveguide Under Inclined Magnetization
Authors: Wu Bao-Jian  , Liu Gong-Qiang  ,   上海交通大学应用物理系，上海 200240
Published: December 2020

The characteristics of magnetostatic forward volume waves (MSFVWs) propagating in magneto-optical (MO) film waveguide under inclined bias magnetic field are analyaed. The dependences of MSFVW propagation constant and dynamic magnetization related to the MO coupling coefficients on mode number, frequency and inclined bias magnetic field are calculated in detail. It is shown that the greater the MSFVW frequency f and the mode number m as well as the less bias magnetic field Hi and inclination θ, the greater MSFVW propagation constant Ks is; the amplitude of zero-mode MSFVWs is much greater than that of high-mode MSFVWs. In an appropriate frequency range, MSFVW amplitude can be increased under an inclined bias magnetic field, and then the diffraction efficiency of guided optical waves with MSFVWs is improved.
Studies on A Freshwater Magnetotactic Coccus
Authors: Wu Xiao-Ling  , Du You-Wei  ,   (1)南京大学物理系，固体微结构物理国家重点实验室，南京 210093; (2)南京大学物理系，固体微结构物理国家重点实验室，南京 210093；南京医科大学物理教研室，南京 210029
Published: December 2020

We report a previously undescribed magnetic coccus, designated NMC-1, that was present in surface sediments collected from the pool in Nanjing suburbs. They orientated and navigated along geomagnetic field lines. Transmission electron microscope photographs showed that the NMC-1 contained over ten magnetosomes. The individual mature crystal was 70nm in length and 40nm in width, which were within the calculted stability field for single-domain magnetite. The energy profile of X-rays was collected after electron excitation of the magnetosomes within a single cell. Iron was the predominant detectable element in the particles. Electron diffraction pattern indicated the magnetosomes are single crystals.
ANNEALED CRYSTALLIZATION OF ULTRAFINE Ni-P AND Ni-Ce-P AMORPHOUS ALLOYS STUDIED BY XAFS
Authors: SUN JIAN-WEI  , WANG XIAO-GUANG  , YAN WEN-SHENG  , XU FA-QIANG  , LIU WEN-HAN  , CHEN CHA NG-RONG  , WEI SHI-QIANG  ,   (1)中国科学技术大学国家同步辐射实验室，合肥  230029; (2)中国科学技术大学国家同步辐射实验室，合肥  230029；中国科学技术大学天文与应用物理系，物理系，合肥  230026
Published: December 2020

XAFS technique has been used to quantitatively determine the local structure evo lutions of ultrafine Ni-P and Ni-Ce-P amorphous alloys prepared by chemical redu ction during the annealing process.Using an asymmetric atom distribution functio n model of convolution of a Gaussian function PG and an exponential f unction PE for XAFS data analysis,we obtained that the average bond l ength Ｒj,coordination N,thermal disorder factor σT,and s tatic disorder factor σS for the Ni-Ni first neighbor shell are 0.27 1nm,10.0,0.0060nm and 0.028nm in the Ni-P and 0.271nm,10.6,0.0070nm and 0.030nm in the Ni-Ce-P initial samples,respectively.It indicates that the σS is rather large and about three times larger than that of σT.The Ni -P sample crystallized under the annealing temperature of 573K,while the crystal lizing temperature of Ni-Ce-P sample is about 100K higher.The result suggests th at the thermal stability of Ni-Ce-P sample is significantly increased by the add ition of 2% Ce element.After being annealed at 773K,both Ni-P and Ni-Ce-P sample s are fully crystallized as metallic Ni and an amount of crystalline Ni3P.Furthermore,we have found that the static disorder σs of Ni-Ni coordination shell is 0.011nm for the Ni-P and still larger for the Ni-Ce-P samp les annealed at 773K,despite their radial distribution functions around Ni atoms are similar to that of Ni foil.It implies that the Ni lattice obtained from the crystallized Ni-P and Ni-Ce-P amorphous alloys is significantly distorted by th e interaction of P element.
THE DESORPTION AND DISSOCIATION OF ETHYLENE (C2H4) ON Ru(1 010) SURFACE
Authors: ZHUANG YOU-YI  , WU  YUE  , ZHANG JIAN-HUA  , ZHANG HAN-JIE  , WANG JIAN  , LI HAI-YANG  , HE PI-MO  , BAO SHI-NING  ,   浙江大学物理系，杭州  310027
Published: December 2020

The ethylene (C2H4) adsorbed on Ru(1010) surface has been studied by X-ray photoelectron spectroscopy (XPS),thermal desorption spectroscop y (TDS) and ultraviolet photoelectron spectroscopy (UPS).The results show that e thylene absorbs in molecular state on Ru(1010) surface stably below 200K.The deh ydrogenation of ethylene occurs at 200K.The main product of the dehydrogenation of the absorbed ethylene is the acetylene (C2H2). After th e dehydrogenation of the absorbed ethylene,the C1s shifts 0.3eV to low binding e nergy level,and the binding energies of σCC and σCH bond have an increase of 0.5eV and 1.1eV respectively.
SELF-CONSISTENT CALCULATION OF ATOMIC STRUCTURE FOR MIXTURE
Authors: MENG XU-JUN  , ZONG XIAO-PING  , BAI YUN  , SUN YONG-SHENG  , ZHANG JING-LIN  ,   (1)北京应用物理与计算数学研究所，北京  100088; (2)河北大学电信学，保定  071002
Published: December 2020

Based on relativistic Hartree-Fock-Slater self-consistent average atomic model,atomic structure for mixture is studied by summing up component volumes in mixture.Algorithumic procedure for solving both the group of Thomas-Fermi equations and the self-consistent atomic structure is presented in detail,and,some numerical results are discussed.
SCALING BEHAVIOURS OF VORTEX TRANSPORT IN 2H-Nb0.9Ta0.1Se2
Authors: ZHANG BO  , TIAN MING-LIANG  , ZHANG YU-HENG  ,   中国科学技术大学结构分析开放实验室,合肥230026
Published: December 2020

The field dependence of voltage V(H) in a 2H-Nb0.9Ta0.1Se2 single crystal at various currents was measured and converted to current-voltage data V(I). Then the scaling law V=α(I-Ic)β was applied to extract the critical current Ic(H) and differential resistance Rd(H). The results show a peak on the differential resistance vs.H curve near Hc2 when the applied current is high, but for a lower current it appears near the onset of peak effect region. This indicates that the new types of pinning centers generated by doped Ta significantly alter the dynamic properties of the vortex system.
AN EXPERIMENTAL STUDY ON THE FLUORESCENCE CORRELATIONSPECTROSCOPY IN LASER GRADIENT FIELD
Authors: DING YAO  , MENG FAN-BO  , CHEN BO  , MA HUI  , JIN LEI  , CHEN DIE-YAN  ,   清华大学物理系,原子分子纳米科学国家教育部重点实验室,北京100084
Published: December 2020

This work studies experimentally the influence of a laser gradient field on fluorescence correlation spectroscopy measurements.Results show that the derived diffusion time for particles across the detection volume increases almost linearly with the strength of the gradient field.The derived number of fluorescing particles in the detection volume also increases with the field.The larger the polarizability of the particles,the bigger the effects of the gradient field.
CALCULATION OF THE LARGEST LYAPUNOV EXPONENT IN THE DISCRETE DYNAMICAL SYSTEM WITH WAVELET ANALYSIS
Authors: LIU HAI-FENG  , ZHAO YAN-YAN  , DAI ZHENG-HUA  , GONG XIN  , YU ZUN-HONG  ,   华东理工大学资源与环境工程学院,上海200237
Published: December 2020

The largest Lyapunov exponent is an important parameter of detecting and characterizing chaos produced from a dynamical system. Based on simulative calculation, it has been found that the largest Lyapunov exponent of the small scale wavelet transform modulus of a discrete dynamical system is the same as the system's. At the same time, the calculated results show that calculating the largest Lyapunov exponent with the small scale wavelet transform modulus can efficiently eliminate the effect of strong large scale noiss because of the high pass filtering characteristic of small scale wavelet transform.