bluuebunny/crossref_metadata_2025 huggingface dataset:
VARIATION OF INTERCHAIN POTENTIAL DURING MOLECULAR CHAIN ROTATION IN POLY (VINYLIDENE FLUORIDE)
Authors: XU JING  , LI JIE  ,   同济大学物理系：波耳固体物理研究所，上海  200092
Published: December 2020

The variation of interchain potential in poly (vinylidene fluoride) polymer during chain rotation was calculated.In the case that center chain rotates while all other chains keep static as discussed by “six-site-potential” theory,the potential curves show four high potential barriers owing to the steric effect of fluorine atom from adjacent molecule,which is in contrast to the six-fold sysmmetry pre-dicted by the “six-site-potential” model.It was found that if all chains rotate synchronically, the barrier height will reduce dramatically.The result also indicates that the polarization reversal is ac-complished with the change of lattice constant.The finally obtained barrier height is about 7.5kJ/mol.In comparison with the thermal energy of chain rotation at room temperature (about2.5kJ/mol),the potential well is too shallow to form stable spontaneous polarization.It was specu-lated therefore,the formation of spontaneous polarization in these materials should include some ex-ternal factors.
TWO-DIMENSIONAL LOCALIZED VIBRATIONAL MODES OF POLYTHIOPHENE AROUND AN ELECTRONIC BIPOLARON
Authors: XIE ZUN  , AN ZHONG  , LI YOU-CHENG  ,   (1)河北师范大学物理系，石家庄  050016; (2)河北师范大学职业技术学院电子系，石家庄  050031; (3)香港中文大学物理系，香港
Published: December 2020

In consideration of the influence of a planar polythiophene configuration,we study the localized vibrational modes around an electronics bipolaron by using a two-dimensional SSH model.Fifteen lo-calized vibrational modes have been found,among them,four infrared active localized vibrational modes and four Raman active ones could be used to interpret the four observed intense infrared ab-sorption lines at 1020,1120,1200 and 1323 cm-1,and the four Raman active absorption peaks at 700,1047,1175 and 1220 cm-1,respectively.
SOLITONS IN INHOMOGENEOUS PLASMAS
Authors: LV KE-PU  , DUAN WEN-SHAN  , ZHAO JIN-BAO  , WANG BEN-REN  , WEI RONG-JUE  ,   (1)南京大学声学研究所，南京  210093; (2)西北师范大学物理系，兰州  730070
Published: December 2020

Propagation of solitons is investigated on an inhomogeneous plasmas that contain two kinds of ions with different masses.The nonlinear acoustic waves can be described by either KdV-type equation or Nonlinear Schrdinger equation in the lowest order.The amplitudes,propagating velocities or wave shapes of these quasi-solitons are analytically given in this paper.
A NEW TWO-WAY TRAVERSABLE WORMHOLE SOLUTION FOR VACUUM BRANS-DICKE EQUATIONS
Authors: HE FENG  , LIU JIN-WANG  , LIU LIAO  ,   (1)北京师范大学物理系，北京  100875; (2)湘潭师范学院数学系，湘潭  411100; (3)湘潭师范学院物理系，湘潭  411100
Published: December 2020

It is shown that a new set of exact solutions in vacuum Brans-Dicke theory is obtained and it admits wormhole geometry.Two-way traversable wormholes in the Brans-Dicke theory is allowed for the coupling parameter ω(-2≤ω≤0) and the appropriately chosen integration constants.It also follows that the scalar field  plays the role of exotic matter and this violates the weak energy condition.
SYNCHRONIZING CHAOS BY DRIVING OF DISCRETE CHAOTIC SIGNAL
Authors: LUO XIAO-SHU  , FANG JIN-QING  , WANG LI-HU  , KONG LING-JIANG  , WENG JIA-QIANG  ,   (1)广西师范大学物理与电子科学系，桂林  541004; (2)中国原子能科学研究院，北京  102413
Published: December 2020

In this paper, the method of synchronizing chaos by driving of discrete chaotic system in continuous chaotic systems is proposed. The logistic map, Henon map and the system of Lorenz are taken as three typical examples. The simulation results show that two continuous chaotic systems can be synchronized completely when the strength of the driving signal is large enough and the spectrum of the output signal is similar to the spectrum of white noise. At the sametime, we have studied the possibility of secrete communication based on the method proposed in this paper.
VARIOUS HYSTERESIS LOOPS AND MULTISTABILITY ON OUTPUT CURVES OF TUNABLE EXTERNAL CAVITY SEMICONDUCTOR LASERS
Authors: WANG GUAN-ZHONG  , YE FENG  , CHANG CHAO  , ZHANG YING-HUI  , FANG RONG-CHUAN  ,   (1)中国科学技术大学化学物理系，合肥  230026; (2)中国科学技术大学结构分析开放实验室，合肥  230026；中国科学技术大学物理系，合肥  230026; (3)中国科学技术大学物理系，合肥  230026
Published: December 2020

Micro-Raman analyses were carried out to investigate the micro-structure of cross section for diamond films prepared by hot-filament chemical vapor deposition.The variation of Raman peak feature with position was recognized as the difference of micro-structure in the film.The presence of broad band and high background intensity near the substrate surface was attributed to the amorphous carbon synthesized in the nucleation process of diamond film.The reduction of sp3-bond structure in the amorphous carbon phase was used to account for the observation of the 1200—1600cm-1 band intensity declination as the increase of film thickness.From the Raman feature it was shown that the sp2-bond structure and the graphitic phase decreased slowly,compared with the bond structure in the growth process of the film.The micro-Raman spectroscopy obtained by scanning parallel to the surface of the film showed the structure and composition difference between the diamond grain and the grain boundary.
Magnetostriction of TbyDy1-y(Fe1-xTx)2(T=Al,Mn) and Their Intrinsic Magnetostrictive Properties
Authors: Li Yang Xian  , Qu Jing-Ping  , Wang Bo-Wen  , Xu Gui-Zhi  , Yu Hui  , Yang Qing-Xin  , Yan Wei-Li  , Wu Guang-Heng  , Wang Jing-Hua  , Tang Cheng-Chun  , Zhan Wen-Shan  ,   (1)河北工业大学材料工程系，天津 300130; (2)中国科学院物理研究所磁学国家重点实验室，北京 100080
Published: December 2020

Magnetostriction of TbyDy1-x(Fe1-xTx)2(T=Al,Mn) single crystals, prepared by the MCGS-3 CZ instrument, was investigated. The intrinsic magnetostrictive properties were derived by fitting method of X-ray diffraction patterns of polycrystal samples prepared by arc-melting method. The substitution of AL, Mn for Fe lowers the saturation field and magnetocrystalline anisotropic energy. The intrinsic magnetostriction, 111, decreases with increasing amount of Al or Mn. For Tb0.5Dy0.5(Fe0.9Mn0.1)2 single crystals,a large magnetostriction and high d33 can be obtained under the compressive stress of 1226 MPa.
NONLINEAR FEEDBACK FOLLOWING CONTROL OF CHAOTIC SYSTEMS
Authors: WU WEI-GEN  , GU TIAN-XIANG  ,   (1)电子科技大学自动化系，成都  610054; (2)电子科技大学自动化系，成都  610054；攀枝花大学电气工程系，攀枝花  617000
Published: December 2020

A new nonlinear feedback following controlling method of chaotic systems is presented to stabilize chaotic systems and follow a deteministic motion. Theory and experiments show this controlling method is strongly robust.
MAGNETO-OPTICAL PROPERTIES OF Pt1-xMnx/Co MULTILAYERS
Authors: LIANG BING-QING  , CHEN XI  , ZHOU XUN  , LIU HONG  , WANG HAI  , TANG YUN-JUN  , WANG YIN-JUN  , WANG SONG-YOU  , CHEN LIANG-YAO  ,   (1)复旦大学物理系，上海  200433; (2)贵州师范大学物理系，贵阳  550001; (3)首都师范大学物理系，北京  100037; (4)中国科学院物理研究所磁学国家重点实验室和凝聚态物理中心，北京  100080
Published: December 2020

The polar Kerr rotation, Kerr ellipticity and optical constant n and k change regularly with the increase of Mn doping in Pt layer of Pt/Co multilayers. Through calculation and analyses, in heavy Mn doping the change of the Kerr rotation is due to the off-diagonal elements of dielectric tensor. However, in light Mn dop ing the change of Kerr rotation results from the change in the magneto-optical a nd optical constants. The enhanced magneto-optical Kerr rotation is due to the e nhancement of Pt spin-orbit coupling. The variation of Pt spin-polarization resu lts in the change of diagonal and off-diagonal elements of dielectric tensor.
DOUBLE-WAVE DESCRIPTION OF THE MOTION OF SPINNING ELECTRON IN BOTH ELECTROMAGNETIC FIELD AND TWO-DIMENSIONAL HARMONIC OSCILLATOR POTENTIAL FIELD
Authors: WU QI-XUE  ,   漳州师范学院物理系，漳州  363000
Published: December 2020

Quantum theory of double-wave function description (DWFD) is applied to describe the motion of spinning electron in both perpendicular uniform electromagnetic field and two-dimensional harmonic oscillator potential field.The time evolution equations of related mechanical quantities are derived.Furthermore,DWFD of spin-zero electron in the same fields is also given,and it is found that their classical limit results correspond to those of classical mechanics.
CHARACTERISTICS AND RESPONSE RATE OF STIMULATED PHOTOREFRACTIVE SCATTERING SELF-PUMPED PHASE CONJUGATOR IN RARE-EARTH DOPED BaTiO3
Authors: XU XIN-GUANG  , DU CHEN-LIN  , SHAO ZONG-SHU  , MU XIAO-DONG  , HU JU-GUANG  , XU HAI-QING  , LUO HAO-SU  , ZHONG WEI-ZHOU  ,   (1)山东大学晶体材料国家重点实验室，济南  250100; (2)中国科学院上海硅酸盐研究所，上海  201800
Published: December 2020

Characteristics and response times of the stimulated photorefractive scattering self-pumped phase conjugator(SPS-SPPC) in the series of Rh-doped and Ce-doped BaTiO3 crystals are investigated.The experimental results show that the SPS-SPPC has higher reflectivity and faster response rate at greater incident angle.The phenomenon was properly analysed using characteristics of two-wave mixing.By the way,the phase conjugation reflectivity of Ce:BaTiO3 is higher than that of Rh:BaTiO3 crystals'.
CONFIGURATION OF MAGNETIC FIELDS INDUCED BY SUPERTHERMAL ELECTRONS
Authors: CHEN ZHENG-LIN  , ZHANG JIE  ,   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

Charge separation electric fields and magnetic fields induced by superthermal electrons escaping from the plasmas have been evaluated using a very simple model. The magnitude and configuration of magnetic fields have been obtained. Generally the circular-shaped magnetic fields are weak because of the charge separation electric field and the followed finite number of the escaping superthermal electrons, and they are mainly distributed over the laser focus near the surface of the plasma because of the transverse motion of the escaping superthermal electrons. Only when electron current is very strong (about 103A through the cross-section with 1μm radius) a 102T magnetic field can be obtained.
PHOTOEMISSION ENHANCEMENT OF Ag-BaO THIN FILMS WITH INTERNAL FIELD-ASSISTED STRUCTURE
Authors: ZHANG QI-FENG  , WU JIN-LEI  ,   北京大学电子学系，北京  100871
Published: December 2020

The Ag-BaO photocathode with internal field-assisted structure was successfully fabricated through depositing silver electrode on the surface of Ag-BaO thin film. Photoemission enhancement was observed when the internal field-assisted bias was applied to the Ag-BaO thin film. Theoretical analysis shows that enhanced photoemission can be attributed to the decrease of interfacial barrier between Ag particles and BaO matrix, and the degradation of vacuum level at the surface.
THE FORMATION AND CHARACTERISTICS OF Si1-xCx ALLOYS IN Si CRYSTALS BY MEANS OF IMPLANTATION OF CIONS WITH DIFFERENT DOSES
Authors: WANG YIN-SHU  , LI JIN-MIN  , JIN YUN-FAN  , WANG YU-TIAN  , LIN LAN-YING  ,   (1)北京师范大学物理系，北京  100875; (2)中国科学院半导体研究所，北京  100083; (3)中国科学院近代物理研究所，兰州  730000
Published: December 2020

Carbon ions with concentration of (0.6—1.5)% were implanted into silicon crystals at room temperature and Si1-xCx alloys were grown by solid phase epitaxy with high temperature annealing. The formation and characteristics of Si1-xCx alloys under different implanted carbon doses were studied. If the implanted carbon atom concentration was less than 0.6%, carbon atoms would tend to combine with the defects produced during implantation and it was difficult for Si1-xCx alloys to form during annealing at 850—950℃. With the increase of implanted C concentration, almost all implanted carbon atoms would occupy substitution positions to form Si1-xCx alloys, but only part of implanted carbon atoms would occupy the substitution position to form Si1-xCx alloys as the implanted dose increased to 1.5%. Most Si1-xCx alloy phases would vanish as the annealing temperature was increased higher.
A NONLINEAR SIMULATION ON BEAM-WAVE INTERACTION FOR HIGH-HARMONIC COMPLEX CAVITY GYROTRON WITH RADUAL TRANSITION
Authors: YU SHENG  , LI HONG-FU  , XIE ZHONG-LIAN  , LUO YONG  ,   电子科技大学高能电子研究所，成都  610054
Published: December 2020

Starting from the general transmission line equation with an electron beam, a se lf-consistent nonlinear analysis on complex cavity gyrotron with gradual transit ion is presented, in which the multiple modes interacting with an electron beam and the mode coupling are taken into account. The interaction between the electr on beam and H51-H52 RF field for third-harmonic gyrotron i s simulated numerically. The influences of multiple modes on the interaction are analyzed.
DIRECT CHAOS TOWARDS LOW PERIOD MOTION BASED ON NOTCH FILTER FEEDBACK CONTROL
Authors: CAI CHAO-HONG  , XU ZHEN-YUAN  , XU WEN-BO  ,   无锡轻工大学信控学院,无锡214036
Published: December 2020

A method is presented here to direct the chaotic motion towards desired low-period motion by using notch filter output feedback control in lots of chaotic systems. The mathematic and physical mechanism of this method is also discussed based on Melnikov Method which is perturbation criteria for chaos. The control results of some typical chaotic systems are given, which has been shown that the method of controlling chaos can be easily and practically realized in physical systems. The method, furthermore, can be applied to achieve control for hyper-chaotic systems.
THE ATOMIC EMISSION PROBABILITY OF THE MICROMASER WITH KERR MEDIUM
Authors: WU SHU-DONG  , QU ZHAO-JUN  , ZHAN ZHI-MING  , JIN LI-XIA  ,   华中科技大学物理系,武汉430074
Published: December 2020

In this paper, we establish the general quantum theory of the micromazer with Kerr medium. When a two-Level atom enters into the Kerr medium cavity field of a coherent state via z motion, we analyze and calculate the atomic emission probability of different regimes (thermal-atom and ultracold-atom regimes).The influence of coupling constant χ,detuning Δ and the atomic injection rate r on the atomic emission probability is discussed emphatically.
MISALIGNED FRACTIONAL FOURIER TRANSFORMS AND THEIR OPTICAL IMPLEMENTATION
Authors: ZHAO DAO-MU  , WANG SHAO-MIN  ,   浙江大学物理系,杭州310028
Published: December 2020

Based on the misaligned diffraction integral formula for misaligned optical systems, the diffraction for misaligned Lohmann's fractional Fourier transformation system and quasi-asymmetrically inhomogeneous medium are analysed, respectively. It is found that there exist similar expressions of misaligned diffraction integral formula and they are essentially equivalent. And also, a new concept of misaligned fractional Fourier transform is put forward.
INVESTIGATION OF THE LONGITUDINAL MOTION OF ELECTRONS IN THE PLASMAS WITH ULTRA-INTENSE LASER PULSE
Authors: HE BIN  , CHANG TIE-QIANG  , ZHANG JIA-TAI  , XU LIN-BAO  ,   北京应用物理与计算数学研究所,北京100088
Published: December 2020

On the basis of numerical solution of Maxwell equations and fluid motion equations in 1-dimension, it is obtained that the travelling wave-solution of the longitudinal motion equation of electrons in the plasmas with ultra-intense laser pulse. The influence of electro-static field in the plasmas on the longtudinal motion is also analyzed.
RELATIVISTIC EVEN-ORDER HARMONICS GENERATED IN UNDERDENSE PLASMA
Authors: ZENG GUI-HUA  , ZHU HONG-WEN  , XU ZHI-ZHAN  ,   (1)上海交通大学电子工程系,上海200030; (2)中国科学院上海光学精密机械研究所,上海201800
Published: December 2020

In the self-generated magnetic field produced by ultra-intense laser-plasma interaction or background magnetic field, even relativistic harmonics is excited by the ultra-intense laser propagating in underdense plasma which is magnetized by the self-generated magnetic field or backgroud magnetic field. In this paper, the second harmonics and its parameters are investigated.
A NONLINEAR ANALYSIS ON 8mm BAND THIRD-HARMONIC COMPLEX CAVITY GYROTRON WITH GRADUAL TRANSITION
Authors: YU SHENG  , LI HONG-FU  , XIE ZHONG-LIAN  , LUO YONG  ,   (1)成都电子科技大学高能电子研究所,成都610054; (2)襄樊学院物理系,襄樊441002;成都电子科技大学高能电子研究所,成都610054
Published: December 2020

Starting from general transmission line equation with an electron beam, a self-consistent nonlinear simulation on third-harmonic complex cavity gyrotron with gradual transition is presented, in which some practical factors are taken into account. The interaction between the electron beam and- H511-H521 RF field for third-harmonic gyrotron is simulated. The influences of the thickness and the velocity spread and the velocity ratio of the electron beam and the fluctuation of the magnetic field on the multi-modes interaction with an electron beam are analyzed.
STUDY ON THE RESISTIVITY AND HALL EFFECT OF MgB2 AND Mg0.93Li0.07B2
Authors: LI HUI-LING  , RUAN KE-QING  , LI SHI-YAN  , MO WEI-QIN  , FAN RONG  , LUO XI-GANG  , CHEN XIAN-HUI  , CAO LIE-ZHAO  ,   中国科学技术大学结构分析开放实验室,物理系,合肥230026
Published: December 2020

The temperature dependences of resistivity and Hall coefficient of MgB2 and Mg0.93Li0.07B2 were measured, and the temperature dependence of cot-ΘH was calculated. The result of resistivity indicates that MgB2 and Mg0.93Li0.07B2 nearly have the same transition temperature. The-possible effect on transition temperature has been discussed. The measurement of Hall coefficient suggests the type of charge carriers is hole, and the Hall coefficient of Mg0.93Li0.07B2 becomes a little smaller compared with that of MgB2 which is attributed to Li doping . Both the decrease with increasing temperature-and-the temperature dependence of cotangent of Hall angle are proportional to the square of temperature.
EXPLICIT EXACT SOLUTIONS TO NONLINEARCOUPLED DIFFERENTIAL EQUATIONS
Authors: LI ZHI-BIN  , YAO RUO-XIA  ,   (1)华东师范大学计算机科学技术系,上海200062; (2)华东师范大学计算机科学技术系,上海200062;渭南师范学院计算机科学系,渭南714000
Published: December 2020

A method for constructing explicit exact solutions of coupled ordinary nonlinear differential equations by using the special solutions of Riccati equations is proposed.Two coupled nonlinear differentiall equations are studied using this method,and several new solutions (either functional or parametrical) are explicitly obtained,in addition to rederiving all known solutions in a systematic way.
STRUCTURE AND MAGNETIC PROPERTIES OF Fe62Co8-x(Cr,Mo)xNb4Zr6B20 AMORPHOUSALLOY WITH A WIDE SUPERCOOLED LIQUID REGION
Authors: RONG CHUAN-BING  , ZHAO YU-HUA  , XU MIN  , ZHAO HENG-HE  , CHEHG LI-ZHI  , HE KAI-YUAN  ,   (1)东北大学材料与冶金学院功能材料研究所,沈阳110004; (2)中国科学院金属研究所快速凝固非平衡合金国家重点实验室,沈阳110016; (3)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;东北大学材料与冶金学院功能材料研究所,沈阳110004
Published: December 2020

Fe62Co8-xCrxNb4Zr6B20 and Fe62Co8-xMoxNb4Zr6B20(x=0,2,4, atomic percent) alloy series were chosen to study in this paper based on the three empirical rules of making bulk amorphous alloy. The ribbons, 30μm thick and 5mm wide, were produced by single-roller rapid quenching. The thermal stability, amorphous structure and magnetic properties of these alloys were studied by differential thermal analysis, X-ray diffraction, Faraday magnetic balance and static magnetic measurement. The supercooled liquid region ΔTx of the alloy, which contains 2at% Cr, reaches 85K, but the saturation magnetization σs of these alloys decreases distinctly with increasing Cr or Mo. The saturation magnetization σs and coercive force Hc increase rapidly for the alloys of this series annealed at 973K for 900s because of the precipitation of α-Fe.
OUTPUT FEEDBACK SYNCHRONIZATION FOR A CLASS OF CHAOTIC LUR'E SYSTEMS
Authors: LIU FENG  , REN YONG  , SHAN XIU-MING  , QIU ZU-LIAN  ,   (1)清华大学电子工程系,北京100084; (2)西安交通大学自动控制系,西安710049
Published: December 2020

A new synchronization theorem for a class of chaotic Lur'e systems is proposed. With the last state variable of the drive system as the driving signal,it is proved that the global asymptotic stable synchronization can be attained by a simple linear output error feedback.Taking Chua's chaotic oscillator as an example,simulation results demonstrated the effectiveness of the present control rule.
EFFECT OF LOW-ENERGY DEPOSITION PARTICLES ON INITIAL STAGE OF THIN FILM
Authors: CHEN MIN  , WEI HE-LIN  , LIU ZU-LI  , YAO KAI-LUN  ,   (1)华中科技大学物理系,武汉430074; (2)华中科技大学物理系,武汉430074,岳阳师范学院物理系,岳阳414000
Published: December 2020

The effect of low-energy deposition particles on the initial stage of thin film growth is studied by Monte Carlo simulation in this paper. The energy range of deposition particles is from 0 to 0.7eV. Three processes are considered: atom deposition, adatom diffusion and re evaporation. The effect of nearest adatoms and next near adatoms is also considered. The results show that the low-energy ion irradiation strongly affects the island film growth process at low temperature. Morphologies and size distributions of islands have significantly changed with the increase of incident ion energy.
Stability of the equilibrium state in relativistic Birkhoff systems*
Authors: Fu Jing-Li  , Chen Li-Qun  , Xue Yun  , Luo Shao-Kai  ,   (1)长沙大学数学力学和数学物理研究所,长沙410003; (2)上海大学上海市应用数学和力学研究所,上海200072; (3)上海大学上海市应用数学和力学研究所,上海200072;商丘师范学院数学力学和数学物理研究所,商丘476000
Published: December 2020

The stabilities of the equilibrium state in relativistic Birkhoff autonomous systems, relativistic Birkhoff semiautonomous systems and relativistic Birkhoff nonautonomous systems are studied .The equilibrium state equations are given. The disturbance equation and the first approximate equation are established. The stability criteria for the equilibrium state are obtained. The relationship between the stabilities of the equilibrium state in relativistic Birkhoff systems and classical Birkhoff systems is discussed. Several examples are presented to illustrate the results.
A Study on the double crisis vertex in a twoparameter plane*
Authors: Hong Ling  , Xu Jian-Xue  ,   西安交通大学非线性动力学研究所,西安710049
Published: December 2020

By means of GCMD method, a double crisis of sinusoidally forced oscillators is studied. A double crisis vertex in a two-parameter plane is determined, at which two curves of boundary crisis and two curves of interior crisis meet and four distinct crises coincide. Physically, small parameter perturbation (noise) about such a vertex induces drastic changes in the dynamical behaviour.
Dielectronic recombination from Fe like Au^53+ to Ga like Au^47+ ions*
Authors: Yi You-Gen  , Zheng Zhi-Jian  , Yan Jun  , Li Ping  , Fang Quan-Yu  , Qiu Yu-Bo  ,   (1)北京应用物理与计算数学研究所,北京100088; (2)湘潭师范学院物理系,湘潭411201; (3)中国工程物理研究院,高温高密度等离子体物理国家重点实验室,绵阳621900
Published: December 2020

Ab initio calculations of the rate coefficients for dielectronic recombination from Felike Au53+ to Galike Au48+ ions are performed based on Cowan's quasirelativistic multiconfiguration HartreeFockRelativistic code and distorted wave approaches. A large number of single excited states and doublyexcited states are included in the present calculation. Because of the extensive distribution of autoionization state energy levels and complicated cascade effects, the dielectronic recombination rate coefficients at higher Z are different from those at lower Z's. The results indicate that the error between our work and other theories is less then 10% in the diagnosed electron temperature and density. It is feasible to simulate the average ionized state and charge state distributions in a well characterized highly ionized Au plasma.
Three stage polarization mode dispersion compensator capable of compensating second order polarization mode dispersion
Authors: Zheng Yuan  , Yu Li  , Yang Bo-Jun  , Zhang Xiao-Guang  ,   北京邮电大学理学院物理部,123信箱北京100876
Published: December 2020

The impacts of polarization\|dependent dispersion on systems are investigated brefly, based on which we propose a threestage higherorder polarization mode dispersion(PMD) compensation scheme. Theoretical analysis shows that it is capable of compensating polarization\|dependent dispersion and principal states of polarization rotation rate at the same time. The two possible operating points of this compensator are proposed. Numerical results show that the maximum tolerable PMD value after threestage compensation has been improved by 17% per bitslot than that using twostage compensator.
Study on passive Q switched Nd∶YVO—4 laser with GaAs asa passive Q switched component and output coupler
Authors: Liu Qiang  , Gong Ma-Li  , Yan Ping  , Jia Wei-Fu  , Cui Rui-Zhen  , Wang Dong-Sheng  ,   清华大学精密仪器与机械学系,北京100084;
Published: December 2020

Passive Q switched operation of a laser diodepumped laser is studied with a saturable absorber GaAs as a passive Q switched component and F-P output coupler. The Q switched pulse duration is 47ns, pulse repetition rate is 1183 kHz, pulse average power is 430mW, beam quality M 2 is equal to 1 13 and the laser threshold of passive Q switching is 1700mW. We performed numerical calculations of coupled wave equations for the case of GaAs playing the role as mentioned above, discussed the passive Q switched mechanism and the dependence of pulse duration, pulse repetition rate and average power on the pumping rate and laser cavity length, which was in good agreement with the experimental results. A brief and effective technique is provided for compact Q switched solidstate laser having multiple functions.
Influence of metal ions on the morphology and phase composition of titanium dioxide in TiO-2 muscovite nanocomposites*
Authors: Song Gong-Bao  , Liu Fu-Sheng  , Peng Tong-Jiang  , Liang Jing-Kui  , Rao Guang-Hui  ,   (1)中国科学院物理研究所,北京100080; (2)中国科学院物理研究所,北京100080;西南科技大学矿物材料及应用研究所,绵阳621002
Published: December 2020

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Numerical research of twice sampling stochastic resonance for the detection of a weak signal submerged in a heavy Noise
Authors: Leng Yong-Gang  , Wang Tai-Yong  ,   (1)天津大学机械工程学院,天津  300072; (2)天津大学机械工程学院,天津  300072;中国煤炭经济学院计算机系,烟台  264005
Published: December 2020

A new technique, twice sampling stochastic resonance (SR), is proposed, and with this technique, the goal of detecting a weak signal overwhelmed in a noise is r ealized under large parameters in terms of the theory of adiabatic elimination. For the purpose of practical applications, the relative parameters are investiga ted in the detection of a weak signal based on the technique. The numerical simu lation shows that the method presented here is of potential value in the signal analysis and is expected to be applied to the practically measured data processi ng in the future.
Characteristics of phase-only modulation using a reflective liquid crystal on si licon device
Authors: Ge Ai-Ming  , Sui Zhan  , Xu Ke-Shu  ,   复旦大学信息科学与工程学院，光科学与工程系，先进光子学材料与器件国家重点实验室 ，上海  200433
Published: December 2020

This paper discusses the characteristics of phase-only modulation using a reflec tive liquid crystal on silicon(LCOS). The 2×2 Jones matrix method is used as a computational tool to theoretically analyze phase modulation characteristics. Th e system has been constructed for testing of amplitude and phase, in which a He- Ne laser as the light source, testing the wave front phase using an interferomet er. The LCOS displays as a liquid crystal spatial light modulator and its drivin g circuit is controlled by a computer, digital data are sampled by CCD. We have tested the phase modulation of 1024×768 LCOS displays. Given the state of input and output polarizations ,the result of testing our theories by experiment sho w consistency ,so LCOS displays can be used as phase-only modulator.
Investigations of phase stability of R3(Fe1-xCox)29-yCry(R=Gd,Sm) compounds
Authors: Wang Wen-Quan  , Su Feng  , Liu Chun-Jie  , Wang Xue-Feng  , Yan Yu  , Jin Han-Min  ,   (1)吉林大学物理学院，长春  130023; (2)吉林大学物理学院，长春  130023;吉林大学超硬材料国家重点实验室，长春  130023
Published: December 2020

After the Gd3(Fe1-xCox)29-yCry compound was formed, Sm3(Fe1-xCox)29 -yCry compounds were also successfully fabricated. Phase stability of R3(Fe1-xCox)29-yCr y(R=Gd,Sm) compounds was invest igated by x-ray diffraction and magnetic measurements. Atomic radius theory was employed to interpret why the 3∶29 compounds with high Co component had to cont ain more stabilizing elements. Less stabilizing elements are needed for those wi th larger atomic radius. However,a large atom of a stabilizing element augments the lattice parameter of the compound, which is disadvantageous to the stability of the 3∶29 phase. By studying the phase stability of R3(Fe1-x Cox)29-yCry(R=Gd,Sm) compounds, we have fabricated the Gd3(Fe1-xCox )29-yCry(0.4≤x≤1.0; 4.0≤y≤6.5) and Sm3(Fe1-xCox)29-y Cry(0.4≤x≤1.0; 4.5≤y≤7.5)compounds with room-temperature uniaxial magnetocrystalline anisotropy.
A study of directional effect of depth-concentration distribution for implanted heavy ions with low energies in dry peanut seeds
Authors: Xie Jing-Yi  , Zhou Hong-Yu  , Wang Ping  , Ding Xiao-Ji  , Liu Zhi-Guo  , Song Hai  , Lu Ting  , Zhu Guang-Hua  ,   北京师范大学射线束技术与材料改性教育部重点实验室，北京师范大学低能核物理研究所，北京师范大学材料科学与工程系，北京  100875
Published: December 2020

The depth-concentration distribution in dry peanut seeds for implanted V+ at 2 00keV was measured by two-photon laser scanning microscope. It was observed that when the ions were implanted into peanut samples along longitudinal direction a nd transverse direction, the corresponding depth-concentration distribution curv es possess different shapes and characteristics. This is called directional effe ct. The origin of this directional effect was studied primarily.
Color image segmentation based on the principle of maximum degree of membership
Authors: Liang Yan-Mei  , Zhai Hong-Chen  , Chang Sheng-Jiang  , Zhang Si-Yuan  ,   南开大学现代光学研究所,光电子信息技术科学国家教育部重点实验室,天津  300071
Published: December 2020

A new approach of color image segmentation based on the principle of MDM(maximum degree of membership)for fuzzy pattern recognition is reported in this paper. The colors of target and background obtained from the color histogram of the color image can be used to set some color fuzzy-sets, to which, based on the principle of MDM, the degrees of membership of colors of all pixels in the image in these fuzzy sets are calculated to determine their memberships. A MDM-radial basis function neural network is implemented to segment color images with higher speed and efficiency.
Teleportation of a three-particle entangled W state through two-particle entangl ed quantum channels
Authors: Zheng Yi-Zhuang  , Dai Ling-Yu  , Guo Guang-Can  ,   (1)温州师范学院物理与电子信息科学系,温州  325027; (2)温州师范学院物理与电子信息科学系,温州  325027;中国科学技术大学量子信息重点实验室,合肥  230026; (3)中国科学技术大学量子信息重点实验室,合肥  230026
Published: December 2020

We propose a scheme for teleportation of a three-particle entangled W state through two-particle entangled quantum channels. Firstly, the maximally entangled states are taken as quantum channels, then, the case of nonmaximally entangled channels is considered. We find that when the channels are nonmaximally entangled states, by introducing an ancillary qubit and constructing an unitary transformation properly, teleportation of three-particle entangled W state can be implemented with certain probability.
Synchronization in chaotic systems based on resilient controller
Authors: Guan Xin-Ping  , He Yan-Hui  , Wu Jing  ,   (1)燕山大学电气工程学院，秦皇岛  066004; (2)中国矿业大学信息与电气工程学院，徐州  221008;燕山大学电气工程学院，秦皇岛  066004
Published: December 2020

Using the linear output feedback method, we investigate the resilient synchroniz ation for a class of chaotic systems. The influence of uncertainties in controll er itself is weakened. By the LMI (linear matrix inequality) toolbox, the resili ent controller is derived conveniently. Finally, the computer simulation results illustrate the validity of the method and the importance of the research.
Four-dimensional quantum scattering calculations on the D+CD4→CD3+D2 reaction
Authors: Bai Li-Hua  , Zhang Qing-Gang  , Liu Xin-Guo  ,   山东师范大学物理系,济南  250014
Published: December 2020

The dynamics for the D+CD4→CD3+D2reaction have been studied using reduced dimensionality quantum-mechanical theory. By the theory, the reactive polyatomic molecule CD4was treated as a diatomic molecule D—CD 3 , so the system can be treated as a linear atom_diatom reaction, reducing the sy stem to a four_dimensional scattering problem. In calculations, the Hamiltonian of the reaction system has been carried out using the time-dependent wave packet method, and the propagation of wave packets by the split-operator method. The semiempirical potential energy surface which has been developed by Jordan and Gi lbert is employed. The energy dependence of the calculated reaction probability shows oscillatory structures, similar to those observed in abstraction reactions H+H2, H+CH4,etc. The excitation of the stretching vib ration of reac tive molecule D—CD3gives a significant enhancement of reaction pro babilit y, the reaction threshold decreases with the enhancement of the vibrating excita tion. Detailed study of the influence of initial rotational states on reaction p robability shows a strong steric effect. The integral cross sections of translat ional energy for CD4at both v=0 and v=1 at ground rotational state show th at the vibrational excitation significantly enhances the reaction cross section. And the reaction threshold decreases by about 0.2eV, consistent with that of re action probability. The significant enhancement of the reaction probability of r eaction H+CH4at ground state when compared with D+CD4 can be explain ed reasonably in terms of quantum mechanical zero-point energies and the tunneli ng effect.
Time-space diffraction properties of volume holographic grating in doubly doped LiNbO3:Fe:Mn
Authors: Ren Li-Yong  , Liu Li-Ren  , Liu De-An  , Luan Zhu  ,   中国科学院上海光学精密机械研究所，上海  201800
Published: December 2020

By jointly solving the two-centre material equations and the coupled-wave equaions,we set up a dynamic model to study the time-space diffraction properties of the photorefractive volume holograms recorded by two colour light in doubly doped LiNbO3:Fe:Mn crystals.Numerical calculations show that,the time -space diffraction properties of the dynamic volume grating are relevant to the relative spatial phase shift between the index grating and the interference field.The spatial phase shift is defined between -π and π,the energy transferring direction between the two-coupled beams will be reversed with the reversion of the sign of the spatial phase shift.The winding of equal-phase line and the redistributed intensities of the two-coupled beams inside the crystal are given.
The I-V characteristics of nano-silicon/crystal silicon hetero-junction
Authors: Liu Ming  , Liu Hong  , He Yu-Ｌiang  ,   (1)南京大学物理系，南京  210093; (2)苏州科技大学应用物理系，苏州  215000; (3)中国科学院微电子中心，北京  100029
Published: December 2020

The nc_Si∶H/c_S hetero_junction is fabricated and studied using nc_Si∶H films. Its I_V curves have good thermal stability and change little in the temperature range from 20 to 200℃. The existence of a large amount of interfacial states is resoponsible for the good switch characteristics of the nc_Si∶H/c_Si hetero_junction.
Nonlinear surface spin waves on ferromagnetic media with inhomogeneous exchange anisotropy
Authors: Xu Yan  , Xue De-Sheng  , Zuo Wei  , Li Fa-Shen  ,   (1)兰州大学磁学与磁性材料国家教育部重点实验室，兰州  730000; (2)兰州大学磁学与磁性材料国家教育部重点实验室，兰州  730000;中国科学院近代物理研究所，兰州  730000; (3)中国科学院近代物理研究所，兰州  730000
Published: December 2020

The theory of nonlinear surface spin waves in pure-exchange semi-infinite ferrom agnetic media with inhomogeneous exchange anisotropy has been considered by usin g the Landau-Lifshitz equation. For partly pinned pure-exchange ferromagnet, the boun-dary condition for magnatization of this system is derived, and the nonlinear dispersion relation for these waves is obtained. The one-dimensional(stationary wave along the z-direction) and two-dimensional(2D)(travelling wave in the oxy plane) nonlinear Schrdinger equations which are satisfied by the spin -wave envelope amplitude of the magnetization, are derived. It is shown that the amplitude of the magnetization is determined by the 2D nonlinear Schrdinger e quation. From this, we predict that the nonlinear excitation on the surface of m agnetic materials should be of 2D soliton form. For weakly nonlinear spin waves, the possibi-lity of soliton formation on the basis of 2D nonlinear Schrdi nger equation has been discussed in detail.
Calculations of the spin-polarization of the electronic current injected from a ferromagnetic metal into a semiconductor
Authors: Li Tong-Cang  , Liu Zhi-Jing  , Wang Ke-Yi  ,   (1)中国科学技术大学近代物理系，合肥  230026; (2)中国科学技术大学精密机械与精密仪器系，合肥  230027
Published: December 2020

In this paper, we calculate the relationships both between the width of the tunnel barrier and the spin-polarization(SP) of the electronic current when it is injected from a ferromagnetic metal into a semiconductor through a tunnel barrier and between the bias and SP. The results agree with the latest experimental results. We found that a moderate bias and tunnel barrier width allow a giant SP and there is little spin injection at very low bias.
Affect of the orbital ordering in half-doped manganites on their optical propert ies
Authors: Shu Zheng-Huang  , Dong Jin-Ming  ,   (1)南京大学物理系，南京  210093; (2)南京大学物理系，南京  210093;江苏广播电视大学，南京  210013
Published: December 2020

Based on the two-orbital double-exchange model, we discuss the affect of the on- site Coulomb interaction on the orbital ordering in hafl-doped manganites and de rive a formula of the optical conductivity for various phases of half-doped mang anites. The results show that there exists a correlation between the orbital ord ering and the optical absorption. For the magnetic phase (FM), with the transiti on from orbital-disordered to orbital-ordered states induced by the on-site Coul omb interaction(U),the incoherent optical absorption we calculate is substantial ly different. For the layered antiferromagnetic phase (A), the increase of the o n-site Coulomb interaction enlarges the orbital ordering. As a result, the energ y gap in the incoherent absorption is also widened.
Solid state diffusion of NaCl into NaY zeolite studied by positron annihilation
Authors: Zhu Jun  , Wang Li-Li  , Ma Li  , Wang Shao-Jie  ,   武汉大学物理系，武汉  430072
Published: December 2020

A series of samples, prepared from mechanical mixtures of NaCl with NaY zeolite and resulting in the dispersion of NaCl in NaY, was studied by position annihila tion spectroscopy. We measured the positron lifetime spectroscopy as a function of the weight ratio of the NaCl-NaY zeolite heated at 500℃ for 1h, as a function of the heating temperature held for 1h, and as a function of the heating duration at 500℃ for NaCl/NaY(15%). All the lifetime spectra were resolved into five components, in which the third, fourth and fifth components are related to the positron annihilation in β cage, supercage and interface void respectively. The experimental results showed that position annihilation spectroscopy is sensitiv e to the change of the dispersion of NaCl in NaY zeolite.
Form invariance and Lie symmetry of relativistic mechanical system
Authors: Fang Jian-Hui  , Chen Pei-Sheng  , Zhang Jun  , Li Hong  ,   石油大学应用物理系，东营  257061
Published: December 2020

We study the form invariance and Lie symmetry of a relativistic mechanical syste m. Firstly, we give the definition and criterion and conserved quantity of the f orm invariance and Lie symmetry in the system. Next, the relation between the fo rm invariance and Lie symmetry of the system is obtained. Finally, we give an ex ample to illustrate the application of the result.
Exact solution for a harmonic oscillator with a time-dependent inverse square po tential by path-integral
Authors: Wang Ping  , Yang Xin-E  , Song Xiao-Hui  ,   天津大学理学院应用物理系，天津  300072
Published: December 2020

Using coordinate-transformation we transformed a harmonic oscillator with time-d ependent mass and a time-dependent inverse potential into a harmonic oscillator with time-independent mass and a time-independent inverse potential accordingly. In terms of the relation between these two different harmonic oscillators' prop agators we derived the exact wavefunction of the former by Feynman path-integral . We also discussed the harmonic oscillator with more additional potentials.
The uncertainty relations and minimum uncertainty states
Authors: Deng Wen-Ji  , Xu Yun-Hua  , Liu Ping  ,   (1)华南理工大学材料科学研究所，广州  510640; (2)华南理工大学物理系，广州  510640
Published: December 2020

Based upon some basic properties of Hermitian operators and Hilbert state vector s, the Heisenberg's uncertainty relations are analyzed in details. The necessary and sufficient condition for the minimum uncertainty states is re-obtained dire ctly from our proof. We propose also the problem of squeezed states for any coup le of dynamical variables, and solve it by using the bosonic creation and annihi lation operators.
The characters of riddled basins in coupled chaotic synchronized maps with addit ive noises
Authors: Tan Ning  , Xu Jian-Xue  , Kang Yan-Mei  , Chen Yong-Hong  ,   西安交通大学机械结构强度与振动国家重点实验室，西安  710049
Published: December 2020

In real systems, because of the inevitable noise, a chaotic synchronized attractor A will turn into a metastable attractor A′ with an average lifetime . We analyze a two-dimensional coupled map with additive noises and find analytica lly that the riddled basin of A′ will disappear when >2T, where T is the duration of an experiment. Acc ording to the characters of the riddled basin without noises, it is found that t he riddled basin will turn into not only a temporal riddled basin but also a reg ular fractal basin. This result is universal in two-dimensional coupled chaotic synchronized maps, and the further numerical calculations can also confirm this point.
The influence of polarized light on fluorescence emission in total internal refl ection microscopy
Authors: Wang Chen  , Yuan Jing-He  , Wang Gui-Ying  , Xu Zhi-Zhan  ,   中国科学院上海光学精密机械研究所强光光学开放实验室，上海  201800
Published: December 2020

Based on Maxwell equations, we have discussed the different evanescent fields made by excitation with different polarized incident fields, and their influence on fluorescence emission. Our analysis showed that the incident light of p-polar ization produces an ellipitically polarized evanescent field; at the same time, the incident light of s-polarization produces a pure s-polarization evanescent f ield. The probability of the excitation of fluorescent molecules by an evanescen t wave varies with the fluorescent molecules orientation, which will in turn res ult in the anisotropic fluorescence emission.
Propagation of flattened-Gaussian beams in uniaxial crystals
Authors: Luo Shi-Rong  , Lü Bai-Da  ,   (1)四川大学激光物理与化学研究所,成都  610064; (2)四川大学激光物理与化学研究所,成都  610064;华中科技大学激光技术国家重点实验室,武汉  430074
Published: December 2020

The propagation of flattened-Gaussian beams(FGBs) in uniaxial crystals is studied based on the paraxial vector theory of the propagation of beams in uniaxially anisotropic media. Analytical propagation equations are derived, which permit us to study the propagation properties of FGBs in unaixal crystals in a simple way. It is shown that the initial circular symmetry of FGBs cannot be kept up, and the state of polarization of FGBs varies during propagation due to the anisotropy of crystals. The spatial evolutions of ordinary and extraordinary components, as well as these in x and y directions in the crystals originating from input FG Bs are illustrated with detailed numerical examples.
A low-pass filter of wide stopband with a novel dual-layer fractal photonic band gap structure
Authors: Liu Hai-Wen  , Sun Xiao-Wei  , Li Zheng-Fan  , Qian Rong  , Zhou Min  ,   (1)上海交通大学电子工程系,上海   200030; (2)上海交通大学电子工程系,上海   200030;中国科学院上海微系统与信息技术研究所,上海   200050; (3)中国科学院上海微系统与信息技术研究所,上海   200050
Published: December 2020

The concept of the photonic bandgap(PBG) is extended to a novel architecture wh ich consists of two fractal PBG plates stacked up in the direction perpendicular to the plane of the substrate. This novel, dual-layer fractal PBG is presented here as the substrate for a microstrip line, and the resulting configuration builds a low-pass filter of wide stop-band. In the specific design, the dual-layer PBG includes two kinds of fractal PBGs with different periodicities in which one fractal PBG consists of a first-order Sierpinski carpet, and the other consists of third-order Sierpinski gasket. Simulated and measured transmission parameters in comparison with the corresponding two filters with monolayer PBG show that the filter with the proposed fractal PBG drastically enhances the width of the stop-band.
Order-disorder transitions and inverse melting in vortex lattices
Authors: Wang Jin  , Zhao Zhi-Gang  , Liu Mei  , Xing Ding-Yu  ,   (1)东南大学物理系,南京  210096; (2)南京大学固体微结构物理国家重点实验室,南京  210093
Published: December 2020

Using Monte Carlo molecular dynamics simulation for a two-dimensional vortex lattice with random pinning, thermal fluctuations and vortex-vortex interactions, we study the order-disorder transition from a Bragg glass to an amorphous vortex glass or a vortex liquid in the pinning strength-temperature phase diagram. In order to determine the order in the vortex lattice, we calculate the static structure factor and evaluate the finite size exponent from the configurations of the vortex lattice. It is found that the Bragg glass region is sandwiched in between the disordered vortex glass phase at lower temperatures and the vortex liquid phase at higher temperatures, exhibiting inverse melting behavior. We attribute the unusual inverse melting behavior to the temperature dependence of the v ortex-vortex interactions.
Spin polarized dependent Hall effect in metallic granular film Fe15.16Ag84.84
Authors: Chen Wei-Ping  , Feng Shang-Shen  , Jiao Zheng-Kuan  ,   (1)浙江台州学院物理系,临海  317000; (2)浙江台州学院物理系,临海  317000;浙江大学物理系,杭州  310027
Published: December 2020

We report the preparation of metallic granular film Fe15.16Ag84. 84, grown on glass substrate and single crystals silicon substrate respectively, u sing magnetron sputtering method. The applied field H dependences of Hall effect and Hall coefficient RH in this specimen have been investigated. We observed the spin-dependent scattering anomalous phenomenon in the applied field H depend ence of Hall voltage UH, which suggests a corresponding relationship with the magnetoresistance. A proper explanation has been given based on spin-dependent s cattering effect or tunneling effect.
Influence of grid voltage on charge storage ability of porous PTFE film electret s
Authors: Wu Yue-Hua  , Xia Zhong-Fu  , Wang Fei-Peng  , Qiu Xun-Lin  ,   同济大学波尔固体物理研究所,上海  200092
Published: December 2020

The influence of grid voltage on charge storage ability of porous polytetrafluoroethylene (PTFE) film electrets has been systematically studied by means of constant voltage corona charging with a grid, thermal pulse technique, open-circu it thermally stimulated discharge current spectra and monitoring the charging cu rrent through samples during the charging. The origin of the influence has been discussed by using the charge dynamic characteristic and microcosmic structure analysis of the materials. It was found that too high a grid voltage may lead to the declination of charge density deposited in the porous sample and enhance th e charge decay, and thus, to the decrease of piezoelectricity and thermal stabil ity of the porous film. For negatively corona charged porous PTFE, excellent cha rge storage ability can be performed at an optimal grid voltage, which will impr ove its piezoelectric activity in the application to the electret piezoelectric sensor film with dipolar space charges.
Control of chaotic systems based on partial variables feedback
Authors: Gao Tie-Gang  , Chen Zeng-Qiang  , Yuan Zhu-Zhi  ,   南开大学信息技术科学学院自动化系，天津 300071
Published: December 2020

The definition of partial variables inverse sequence feedback controller of a chaotic system is proposed. We studied this kind of controller with Chen's chaotic system and get the existing condition of the controller，and extended the conclusion of the related article, so get various controllers of the chaotic system. Numerical simulations are presented to show that chaotic system control based on partial variables feedback is simple and effective.