bluuebunny/crossref_metadata_2025 huggingface dataset:
STUDY OF RELATIVE DOSE-ENHANCEMENT EFFECTS ON CMOS DEVICE IRRADIATED BY STEADY-STATE AND TRANSIENT PULSED X-RAYS
Authors: GUO HONG-XIA  , CHEN YU-SHENG  , ZHANG YI-MEN  , ZHOU HUI  , GONG JIAN-CHENG  , HAN FU-BIN  , GUAN YING  , WU GUO-RONG  ,   (1)西安电子科技大学微电子学研究所,西安710000; (2)西安电子科技大学微电子学研究所,西安710000,西北核技术研究所,西安710024; (3)西北核技术研究所,西安710024
Published: December 2020

The results are presented with emphasis on the relative dose-enhancement factor for complementary metal-oxide semiconductor (CMOS) devices irradiated by steady state and transient pulsed X-rays. With the help of experimental study, sensitive parameter threshold voltage as a function of irradiation dose was obtained. So the equivalent relation of total dose damage is eslablished by comparing the response of devices irradiated by 60Co γ-rays and X-rays. By employing the X-ray transient pulsed sources, the research of X-rays transient upset enhancement effects is carried out using bi-laminate structure. Upset enhancement factor of X-rays are measured. These methods are provided for X-ray radiation hardening technology an effective evaluation method.
PREPARATION OF OPTICAL PROBES FOR SCANNING NEAR-FIELD INFRARED MICROSCOPY BY ETCHING METHOD
Authors: ZHANG LI-YUAN  , LI YONG-GUI  , WANG QIAN-  ,   中国科学院高能物理研究所自由电子激光实验室,北京100080
Published: December 2020

The infrared probe is the pivotal part of scanning near-infrared microscopy. The fabrication methods of it are different according to the different kinds of materials, most popular up to now is the adiabatic pulling of optical fibers during heating with CO2 laser and afterwards chemical etching. In this paper, a method of etching is presented; how to deal with the polymer and to strip away the Se-S layer, and how to etch inner core into a high quality tip are introduced in details. The production of large cone angles and smooth probe is further studied, Finally, we use the Beijing free electron laser as light source, The spectrum signals of GaN varying with different wavelengths were detected and analyzed under the near field condition, and obtained the primary result.
POPULATION TRAPPING PHENOMENA IN A TWO-LEVEL SYSTEM
Authors: LONG DE-SHUN  , NING XI-JING  ,   复旦大学现代物理研究所,上海200433
Published: December 2020

The critical criterion for realizing population trapping is deduced for a two-level system driven by a frequency-modulated laser field in terms of dressed atom model, followed by demonstrating the various population trapping behaviours under different conditions. Detailed numerical solutions of time-dependent Schr?idinger equation are found to be in good agreement with the analytical results.
SOLVING THE EIGENVALUE EQUATION OF AN ISOTONIC OSCILLATOR BY PSEUDO-ANGULAR-MOMENTUM METHOD
Authors: LI WEN-BO  ,   北方交通大学物理系,北京100044
Published: December 2020

A rigorous solution of Schr?idinger equation of an isotonic oscillator is studied by pseudo-angular-momentum method. The effect of the parameter g in the centripetal potential barrier on the domain of effective values for formation of stationary bounded states and the effect of domain of the parameter g on the energy spectrum are discussed in detail. An appropriate and comprehensive formulation of the energy spectrum and analytic expressions of the corresponding eigenstates are presented. The different treatments in the literatures are clarified.
DEALING WITH ABEL INVERSION BY USING LENGENDRE EXPANSIONS
Authors: RUAN HUAI-LIN  , WAN BAO-NIAN  , ZHANG XIAN-MEI  , LIU JIAN-KUN  ,   中国科学院等离子体物理研究所,合肥230031
Published: December 2020

A new method is presented for dealing with weakly asymmetrical Abel inversion in this paper. We separate the integrated quantity into odd and even parts by using Yasutomo′s method. The asymmetric local value is expressed as the product of a weight function and a symmetric local value. The symmetric distribution is expanded into Fourier Lengendre series, and the coefficients of the series are determined by using a least-square-fitting method.
DT FUEL AREAL DENSITY DIAGNOSTIC IN DIRECT-DRIVEN IMPLOSIONS
Authors: YANG HONG-QIONG  , YANG JIAN-LUN  , WEN SHU-HUAI  , WANG GEN-XING  , GUO YU-ZHI  , TANG ZHENG-YUAN  , MU WEI-BING  , MA CHI  ,   中国工程物理研究院核物理与化学研究所,绵阳919信箱212分箱,绵阳621900
Published: December 2020

The diagnostic of DT fuel plasma areal density in the direct-driven implosion experiments on SG-Ⅱ laser facility has been performed by measuring the number of recoil D and T produced by 14MeV neutron′s scattering. The particles of recoil D and T were detected by CR39 solid-state nuclear track detector. The experimental results indicate that the uniformity of laser illuminating affects the compression to a certain extent. The areal density of exploding pusher target is about one order lower than that of ablative-driven target. This means that the compression of ablative-driven target is better than exploding pusher target. There is a strong relationship between areal density and suprathermal electron heating.
ELECTRODEPOSITION OF DIAMOND-LIKE CARBON FILMS FROM ORGANIC SOLVENTS AND EFFECTS OF ANNEALING ON THE FILM STRUCTURE
Authors: GUO DONG  , CAI KAI  , LI LONG-TU  , GUI ZHI-LUN  ,   清华大学材料科学与工程系,北京100084
Published: December 2020

After analyzing the molecular structure of several organic solvents we select methanol, N,N-dimethylformamide (DMF) and acetonitrile as the carbon source to deposit diamond-like carbon (DLC) films on Si plate with a pulse-modulated power. The deposition reaction can be facilitated by increasing temperature or by decreasing separation between the electrodes. The films were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy sequentially. The results showed that the films were typical hydrogenated DLC films. Hydrogen was removed and the primary bonding in the films changed gradually from sp3-bonded carbon to sp2-bonded carbon as annealing proceeded, i.e. the film underwent a graphitization process. Comparing the results of different solvents, we discover that the methyl group of the solvents seems to be the functional group in forming the DLC films.
NUMERICAL SIMULATION OF DENDRITIC GROWTH IN UNDERCOOLED MELT USING PHASE-FIELD APPROACH
Authors: YU YAN-MEI  , YANG GEN-CANG  , ZHAO DA-WEN  , Lü YI-LI  , A. KARMA  , C. BECKERMANN  ,   (1)Department of Mechanical Engineering,the University of Iowa.Iowa City,IA 52242,USA; (2)Department of Physics and Center for Interdisciplinary Research on Complex Systems,Northeastern   University,Boston,Massachusetts 02115,USA; (3)西北工业大学凝固技术国家重点实验室,西安710072
Published: December 2020

Using the phase-field approach, the dendritic growth in the undercooled pure metal melt is simulated, and the dependence of dendritic growth upon the anisotropy,interfacial kinetics,thermal diffusivity and surface energy is investigated.The calculated results indicate that the heat noise can trigger the growth of side-branches;however this dose not influence the selection of the tip operating state.The dimensionless tip velocity increases and the tip radius decreases with the increase of anisotropy. Correspondently,the dimensionless tip velocity decreases and tip radius increases when the interfacial kinetics or thermal diffusivity (when the interface kinetic coeffiecient is less than 1) inreases. The surface energy tends to increase the size of dendrite and keeps the stability of interface under the disturbance of heat noise.The greater the surface energy,the weaker the tendency to form side-branches.
ANOMALOUS MAGNETIZATION PEAK EFFECT IN Bi2Sr2CaCu2O8 SINGLE CRYSTALS
Authors: WANG WEN-HU  , LI SHI-LIANG  , CHEN ZHAO-JIA  , WEN HAI-HU  , XIONG YU-FENG  ,   (1)中国科学院理化技术研究所低温事业部,北京100080; (2)中国科学院物理研究所凝聚态物理中心,北京100080
Published: December 2020

Magnetic hysteresis loops were measured on Bi2Sr2CaCu2O8 single crystals with a vibrating sample magnetometer. An anomalous second magnetization peak was observed between 20 and 40K. The magnetic fields showing peak effect in over-doped crystal were observed to be higher than the optimally doped samples. The disorder-driven transition shifted to lower fields with increasing point disorder. At lower temperatures the quasilattice transformed into a disordered solid as the field was increased above the second magnetization peak. There was not any transition from the ordered solid quasilattice to a disordered solid below 20K in schematic vortex matter phase diagram in BSCCO. The peak effect was a complicated function of magnetic field, temperature and material disorder.
MICROWAVE PERMITTIVITY OF NANO Si/C/N OMPOSITE POWDERS
Authors: ZHAO DONG-LIN  , ZHOU WAN-CHENG  , WAN WEI  ,   (1)西北工业大学凝固技术国家重点实验室,西安710072; (2)西北工业大学凝固技术国家重点实验室,西安710072,北京化工大学碳纤维及复合材料研究所,北京100029
Published: December 2020

The microwave permittivity of nano Si/C/N composite powders suspended in paraffin wax has been studied at the frequency range of 8.2—18GHz. The nano Si/C/N composite powders were synthesized from hexamethyldisilazane ((Me3Si)2NH) (Me:CH3) by a laser induced gas phase reaction. The dissipation factors of the nano Si/C/N composite powders are high at the microwave frequencies. The microwave permittivity of the mixture of nano Si/C/N composite powders and paraffin wax (or other dielectric materials) can be tailored by the content of the composite powders. And ε′, ε″ and tan δ increase with the volume filling factor ( v ) of nano Si/C/N composite powders. The ε′ and ε″ can be effectively modeled using second order polynomials ( ε′, ε″=Av2+Bv+C ). The ε′ and ε″ of the nano Si/C/N composite powders decrease with frequency at the frequency range of 8.2—18GHz. The difference being the microwave resonance is not sharply peaked but rather smeared out over a large frequency range. The promising features of nano Si/C/N composite powders would be due to more complicated Si, C, and N atomic chemical environment than in a mixture of pure SiC and Si3N4 phase. The SiC microcrystallines in the nano Si/C/N composite powders dissolve a great deal of nitrogen. The local structure around Si atoms changes by introducing N into SiC. Carbon atoms around Si are substituted by N atoms. So there exist a large number of charged defects and dangling bonds in the nano Si/C/N composite powders. Thus charged defects and quasi free electrons move in response to the electric field, diffusion or polarization current resulting from the field propagation. The high ε″ and dissipation factor tan δ(ε″/ε′) of Si/C/N composite powders are due to the dielectric relaxation.
DYNAMICS THEORY OF FERROELECTRIC POLARONS
Authors: LI ZHI-QIANG  , CHEN MIN  , SHEN WEN-BIN  , LI JING-DE  ,   中山大学物理系,广州510275
Published: December 2020

Dynamics theory of ferroelectric polarons, which was developed from the shielding theory of ferroelectricity, is used to explain the polarization switch of ferroelectricity. The theoretical results are well consistent with the experimental results of TGS crystal. Based on this theory, the basic physics process of electron emissions from ferroelectricity can be studied.
CURRENT TRANSPORT THROUGH STACKED InAs QUANTUM DOTS EMBEDDED IN A SCHOTTKY BARRIER
Authors: LI HONG-WEI  , WANG TAI-HONG  ,   中国科学院物理研究所,北京100080
Published: December 2020

We have investigated the transport properties of a metal-semiconductor-metal structure containing multi-layers of InAs quantum dots from 77 K to room temperature. Three distinct phenomena are observed in the current voltage( I-V ) curves:the hysteresis loops, current jumps and voltage offsets. Because of the coupling between the multi layered quantum dots, the devices made of these quantum dots exhibit much more complicated phenomenon than the devices containing single-layer quantum dots. The devices may undergo many metastable states and relaxation processes. These processes would induce current jump structures and noise in the I-V curve.
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Authors: Wang Shu-Fang  , Zhu Ya-Bin  , Zhang Qing  , Zhou Yue-Liang  , Chen Zheng-Hao  , Lu Hui-Bin  , Yang Gul-Zheng  ,   中国科学院物理研究所光物理开放实验室,北京100080
Published: December 2020

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Integrating factors and conservation laws for non-holonomic dynamical systems
Authors: Zhang Yi  , Ge Wei-Kuan  ,   (1)湖州师范学院物理系,湖州  313000; (2)苏州科技学院土木工程系，苏州  215011
Published: December 2020

In this paper, we present a general approach to the construction of conservation laws for nonlinear non-holonomic dynamical systems by finding corresponding int egrating factors. The definition of integrating factors for the Routh equations of non-holonomic systems is given, and the necessary conditions for the existenc e of conserved quantities of the non-holonomic dynamical systems are studied in detail. The conservation theorem and its inverse for the systems are established , and an example is given to illustrate the application of the results.
Perturbation to symmetries and adiabatic invariant for systems of generalized c lassical mechanics
Authors: Zhang Yi  , Mei Feng-Xiang  ,   (1)北京理工大学应用力学系，北京  100081; (2)苏州科技学院土木工程系，苏州  215011
Published: December 2020

This paper studies the exact invariants and the adiabatic invariants for systems of generalized classical mechanics in the high-dimensional extended phase space and gives the relations between the invariants and the symmetries of the system s in the space. Based on the concept of high-order adiabatic invariant of mechan ical systems with the action of small disturbance, it presents the form of the h igh-order adiabatic invariant and the conditions for their existence,and establi shes the relationship between adiabatic invariant and symmetrical transformation . In the end of this paper, an example is given to illustrate the application of the results.
Finite size effect in EZ model
Authors: Xie Yan-Bo  , Wang Bing-Hong  , Quan Hong-Jun  , Yang Wei-Song  , Wang Wei-Ning  ,   中国科学技术大学近代物理系及非线性科学中心，合肥  230026
Published: December 2020

The finite size effect in the Eguiluz-Zimmermann (EZ) model is studied. It is found that the finite size effect is very important if the number of the agents N is large enough and the probability of trading among the agents is small enough :a1/N. In this case, the model becomes almost a big single cluster system that includes almost all the agents. For the small clusters, the size distribution c an still satisfy a power law. However, the exponent will change due to the fluct uation effect. For a1/N, it can be proved that the fluctuation effect is not i mportant, hence the mean field theory is correct.
Chaotic systems controlled with perturbed parameters based on washout filter tec hnology
Authors: Zhang Hao  , Ma Xi-Kui  ,   西安交通大学电气工程学院,西安  710049
Published: December 2020

The chaos control methodology based on the washout filter technology is used in chaotic systems both without perturbation and with perturbed parameters. A sufficient condition on controller design with perturbed parameters is presented. Numerical results show that this method is easy to be implemented in engineering, requires little control cost, stabilizes the original unstable fixed points within the chaotic attractor and is robust enough. Thus, it is very suitable for engineering applications.
Potential energy functions and molecular reaction dynamics for LiH, LiO and LiOH
Authors: Luo De-Li  , Meng Da-Qiao  , Zhu Zheng-He  ,   (1)四川大学原子分子物理研究所,成都  610065; (2)中国工程物理研究院,绵阳919信箱71分箱  621900
Published: December 2020

The structures of LiH, LiO and LiOH have been optimized based on the density functional (B3LYP/sdd) method with relativistic effective core potential. The Murrell-Sorbie analytic potential energy functions for LiH and LiO, and the many-body expansion analytic potential energy function for LiOH are derived by using the many-body expansion theory and normal equation fitting methods. The dissociation energies for LiH, LiO and LiOH are calculated from the analytic potential energy functions. Then, the atomic and molecular reaction dynamic processes for the collision of O+LiH(ν=0,j=0) system are investigated with the present potential energy functions by Monte-Carlo quasi-classical trajectory approach. The results show that O+LiH(ν=0,j=0) has no energy threshold, and the dominated product is LiO.
Observation of stimulated Raman scattering of weak-gain Raman modes by means of lasing gain
Authors: Pu Xiao-Yun  , Yang Zheng  , Jiang Nan  , Chen Yong-Kang  , Dai Hong  ,   云南大学物理系,昆明  650091
Published: December 2020

The enhancement of stimulated Raman scattering (SRS) of weak-gain Raman modes is demonstrated by overlapping the Stokes wavelengths of the Raman modes with Dye lasing gain. Four SRS spectral lines related to C-H stretching modes of ethanol in a～10-5mol/L Rhodamine 640-doped ethanol pendant drop can be ob served, which are supported by the lasing gain of Rhodamine 640. The dye lasing is found to be partially and even totally suppressed by the intense SRS of ethanol as the pump intensity increasing from 1.2×108W/cm2 to 3. 3×108W/cm2.
The calculation of triple-differential cross sections of hydrogen atom single-io nization by electrons
Authors: Zhang Cheng-Hua  , Qiu Wei  , Xin Jun-Li  , Nu Ying-Yu  , Wang X iao-Wei  , Wang Jing-Yang  ,   (1)辽宁大学物理系,沈阳  110036; (2)中国科学院金属研究所,沈阳材料科学国家(联合)实验室,沈阳  110036
Published: December 2020

A simple model is proposed to study the ionization of the atomic hydrogen by fast election impact in coplanar asymmetric geometry, making use of the post form of the enery shell transition matrix element and the two-potential formula. By virtue of dividing the full kinetic energy operator, we obtain an approximate solution of the three body problem through the canceling of the motion of two-election mass and exponent factor of relative motion and the approximation of projectile plane wave. TDCS(triple differential cross section) is expressed by the product of two factors,the structure factor T2 and correlation one T12. In this article, the contribution of these factors is investigated using the method of asymptotic series and method.
A new theory of migration of radon and its daughters in the ideal condition and their migration equation
Authors: Le Ren-Chang  , Jia Wen-Yi  , Wu Yun-Ping  ,   (1)成都理工大学核工系，成都  610059; (2)福建师范大学物理系，福州  350007
Published: December 2020

The study of radon release and migration is the basic theoretical issue for rado n measurement, which has a close relationship with extensive applications in geo science, environmental science and so on. In this paper, a new theory of migrati on of radon and its daughters has been discussed. The mechanism of vertical mig ration of radon and its daughters is: after α-particles emitted by radon and it s daughters decelerate, they become He nucleus. The He nuclei can combine with r adon and its daughters and form clusters. Because He is very light, it can make the specific gravity of the clusters lower than their buoyancy in the medium. As a result, the clusters will rise of their own accord. When the specific gravity of the clusters is higher than their buoyancy, the clusters will drop down. The theoretical distribution equation is established to describe radon migration an d proved by experiment as well.
Interaction of a moving two-level atom with a two-mode quantized cavity field
Authors: Chen Ai-Xi  , Wu Shu-Dong  , Jin Li-Xia  , Zhan Zhi-Ming  ,   (1)华中科技大学物理系，武汉  430074; (2)中国科学院武汉物理与数学研究所原子与分子物理实验室，武汉  430071
Published: December 2020

We study the micromaser in a two-mode quantized cavity field injected with a two -level atom. A solution in the dressed state description is presented for the sy stem. We investigate,under the thermal-atom regime, the influence of detuning Δ on the atomic emission probability, when the two-mode quantized cavity field is prepared in different states.
Influence of energy-transfer upconversion effect on the pulse in diode-pumped Cr :YAG passively Q-switched lasers
Authors: Yang Lin  , Huang Wei-Ling  , Qiu Jun-Lin  , Feng Bao-Hua  , Zhang Zhi-Guo  , Volker Gaebler  , Baining Liu  , Hans J. Eichler  ,   (1)Optical Institute,Technical University Berlin,D-10623 Berlin,Germany; (2)华中科技大学激光技术国家重点实验室，武汉  430074; (3)华中科技大学激光技术国家重点实验室，武汉  430074;中国科学院物理研究所物理光学实验室，北京  100080; (4)中国科学院物理研究所物理光学实验室，北京  100080
Published: December 2020

Influence of energy-transfer upconversion (ETU) effect on the output pulse in diode-pumped Cr:YAG passively Q-switched lasers is investigated. Using the ETU theory and Q-switching rate equations, the initial population inversion, the final population inversion and the threshold population inversion at the maximum photon density are achieved. The output pulse width and pulse energy depend on the relation between them. The predicted results are in good agreement with the experimental results. The method of reducing the ETU effect is also discussed and it is useful to optimize this kind of lasers.
A study of Mssbauer spectroscopy of microcrystallization of amorphous Fe7 3.5Cu1Nb3Si13.5B9 irradiated b y a CO2-Laser
Authors: Chen Sui-Yuan  , Liu Chang-Sheng  , Fu Gui-Qin  , Ren Xiao-Yu  , Cai Qing-Kui  ,   东北大学材料与冶金学院，沈阳  110004
Published: December 2020

Microcrystalline phases were produced by laser irradiation on the Fe73.5Cu1Nb3Si13.5B9 amorphous ribbon with a power ranging from 40 to 170W,scaning speed 10mm/s,laser beam spot 20mm. Hyperfine structures of the original and crystallized samples were analyzed by transmission Mssbauer spectros copy. We discovered that the basic parameters of the Mssbauer spectra——isome r shift（IS）, quadrupole splitting（QS） and hyperfine magnetic field（Hhf） ch ange with the laser power. Experimental results show that the magnetic moment re organization of Fe73.5Cu1Nb3Si13.5 B9 amorphous phases has take n place and the atom magnetic moment direction maintains a preferred in-plane or ientation, The average hyperfine magnetic field of the amorphous phase is improv ed because of the microcrystalline phase. The crystallized phase was Fe-Si alloy with a DO3 structure, and the area of its spectral lines is about 2% —3.4%. This is caused by the jump of one electron in Fe atom 3d6 shell int o Si atom 3p2 shell, forming a stability electron group.
Dynamics of polarons and bipolarons in nondegenerate polymers
Authors: Wang Lu-Xia  , Zhang Da-Cheng  , Liu De-Sheng  , Han Sheng-Hao  , Xie Shi-Jie  ,   山东大学物理与微电子学院，晶体材料国家重点实验室，济南  250100
Published: December 2020

We investigate theoretically the dynamic process of polarons and bipolarons in n ondegenerate polymers. In a low field, it is bigger that the carriers are charge d polarons or bipolarons，their lattice configurations and charge densities move together all along. The velocity of polarons is bigger than that of bipolarons in the same system. Both polarons and bipolarons have their saturated velocities .The saturated velocities decrease with the increase of the nondegenerate parame ters. In a high electric field, the electronic states of polarons and bipolaron s are dissociated from their lattice states, and move with high velocities. In t his case, the carriers are electrons rather than polarons or bipolarons.
RBS/channeling study and photoluminscence properties of Er-implanted GaN
Authors: Song Shu-Fang  , Zhou Sheng-Qiang  , Chen Wei-De  , Zhu Jian-Jun  , Chen Chang-Yong  , Xu Zhen-Jia  ,   (1)北京大学技术物理系,北京  100080; (2)中国科学院半导体研究所，北京  100083; (3)中国科学院半导体研究所，北京  100083;中国科学院凝聚态物理中心和表面物理国家实验室，北京  100080
Published: December 2020

The Raman back scattering/channeling technique was used to analyze the damage recovery at different annealing temperatures and to determine the lattice locatio n of the Er-implanted GaN samples. A better damage recovery was observed with in creasing annealing temperature below 1000℃, but a complete recovery of the impl antation damage cannot be achieved. For a sample annealed for at 900℃ 30 min th e Er and Ga angular scans across the axis was measured, indicating that a bout 76% of Er ions occupies substitutional sites. Moreover, the photoluminscenc e (PL) properties of Er-implanted GaN thin films have been also studied. The exp erimental results indicate that those samples annealed at a higher temperature b elow 1000℃ had a stronger 1539nm PL intensity. The thermal quenching of PL inte nsity for samples annealed at 900℃ measured at temperatures from 15K to 300K is 30%.
Coulomb blockade three-valued single-electron memory
Authors: Sun Jin-Peng  , Wang Tai-Hong  ,   中国科学院物理研究所，北京  100080
Published: December 2020

We have designed a novel three-valued single-electron memory.This memory compris es two multiple-tunnel junctions(MTJs) and a single-electron transistor which ac ts as an electrometer.Because the Coulomb gaps of the two multiple-tunnel juncti ons are different,the device have three stable states.It is possible to fabricat e multiple-valued single-electron dynamic random access memories(DRAM)and nonvol atile random access memories(NOVORAM).The memory,which is promising for high fre quency and low power-dissipation,can achieve ultradense data storage.
Sr2(Gd,Ce)2Cu2RuO10 synthesized by a new -type solid-state reaction in the presence of oxygen-water vapor mixed atmosphere and its electric properti es
Authors: Li Ming-De  , Wang Zhong-Bing  , Yang Hong-Shun  , Ruan Ke-Qing  , Cao Lie-Zhao  , Chen Zu-Yao  ,   (1)中国科学技术大学化学系，合肥  230026; (2)中国科学技术大学结构研究开放实验室,合肥  230026;中国科学技术大学化学系，合肥  230026; (3)中国科学技术大学结构研究开放实验室,合肥  230026;中国科学技术大学物理系，合肥  230026
Published: December 2020

Sr_Ru cuprates synthesized via traditional solid_state reaction is always accompanied by the formation of small amounts of SrRuO3 impurity phase with ferromagnetism. In this paper we report that not only the pure phase compound Sr2 GdR uO6 without any ferromagnetic SrRuO3 impurity phase is suc cessfully prepared by means of a new_type reaction of solid state in presence of O2 (or air)_wat er vapor mixed atmosphere，but also RuSr2(Gd,Ce)2Cu2O10(Ru_1222）wit hout any ferromagnetic SrRuO3 impurity phase is further synthesized u nder a re lative low reactive temperature when the Sr2GdRuO6 is used as a precursor. T he authors discuss the formation of the product Sr2GdRuO6 and mechanism of t he new_type reaction of solid state in presence of water vapor in detail. In add ition, the effects of SrRuO3 impurity phase on the electric propertie s of the product Ru Sr2(Gd,Ce)2Cu2O10 is also discussed. It suggests that the water vapor for the new_type solid_state reaction is not beneficial to the tran sformation of SrRuO3 to Sr2GdRuO6, and it is to suppress the formation of SrRuO3 due to the formation of RuO2·nH2O. Thus the amount of SrRuO3 impurity phase in Ru_1222 phase is controlled in the reaction of solid state. I t seems that the presence of a small amount of SrRuO3 impurity phase is favourable for making the Ru_1222 phase superconductive.
Thermodynamic properties of ferromagnetic films in variational cumulant expansi on
Authors: Chen Hong  , Yan Yu-Li  , Mei Hua  ,   西南师范大学物理系，重庆  400715
Published: December 2020

The thermodynamical properties of quantum Heisenberg films are studied in variat ional cumulant expansion. The spontaneous magnetization，internal energy and spe cific heat are calculated to the third order. For a thicknesses below a critical value, the magnetization decreases rapidly as the number of atomic layers is de creased. The internal energy increases with decreasing number of atomic layers at any given temperature, and the specific heat increases below the critical tem perature and decreases beyond the critical temperature with decreasing number o f atomic layers.
A study on the properties of (Bi, La)4Ti3O12- Sr(Bi, La)4Ti4O15 intergrowth ferroelectrics
Authors: Zhu Jun  , Lu Wang-Ping  , Liu Qiu-Chao  , Mao Xiang-Yu  , Hui Rong  , Chen Xiao-Bing  ,   扬州大学物理科学与技术学院，扬州  225002
Published: December 2020

Lanthanum_doped intergrowth ferroelectrics: (Bi,La)4Ti3O 12-Sr(Bi,La)4Ti4O15 (SrBi8-xLaxTi7O27) (x＝0.00, 0.25, 0.50, 0.75, 1.00, 1.25, 1.50) ceramic samples have been prepared by solid_state reaction m ethod. Their structure was analyzed by x_ray diffraction, and their dielectricit y and ferroelectricity were measured. It is found that La doping does not change the crystal structure of Bi4Ti3O12-SrBi4Ti4O15. The coerciv e field (EC) of SrBi8-xLaxTi7O2 7 increases slightly and the remnant polarization (2Pr) increases at first, then decreases with th e increas e of La content. The 2Pr reaches a maximum value of 25.6 μC·cm-2, whe n x is 0.50. The 2Pr increases nearly 60%, but the EC incr eases only about 10%, compared with those of SrBi8Ti7O27. Their temperatures of phase t ransition (TC) decrease with La doping. The TC of SrBi7.5La0.50Ti7O27 is 556 ℃ and shows good thermal stability. As x becomes 1.50, the SrBi7.5La0.50Ti7O27 exhibits a characteristic of relaxor ferroelectrics.
The kinetics simulation of trap depths and capture cross sections of SETs in AgC l microcrystals doped with ［Fe(CN)6］4- complex
Authors: Yang Shao-Peng  , Fu Guang-Sheng  , Li Xiao-Wei  , Geng Ai-Cong  , Han Li  ,   河北大学物理科学与技术学院,保定  071002
Published: December 2020

To describe the photoelectron rise and decay process of AgCl microcrystals doped with ［Fe(CN)6］4-, a kinetics model composed of three in trinsic centres and a shallow electron traps(SETs)is set up, and further more, a set of differential equations is deduced. By solving the differential equations, photoelectron decay curve and photoelectron lifetime that is in accord with the transient microwave photoconductivity experimental data are obtained. Adjusting related simulation parameters, the SET depths and capture cross sections at room temperature for ［Fe(CN)6］4- are obtained and they are 0.115eV and 2 .136×10-17cm2, respectively.
Physical meaning of non-Hermitian Hamiltonian
Authors: Chen Zeng-Jun  , Ning Xi-Jing  ,   复旦大学现代物理研究所,上海  200433
Published: December 2020

A four-level system coupled with lasers is analyzed in terms of dressed-atom model by introducing auto-ionization decay which leads to a non-Hermitian Hamiltonian. The population of the system obtained by means of solving the secular equation of the Hamiltonian is found in good agreement with that from numerical solution of time-dependent Schrdinger equation. This result suggests that non-Hermitian Hamiltonian can be introduced into the framework of quantum mechanics , and the imaginary part of the corresponding eigenvalue represents the populati on decaying of systems.
One way Hash function construction based on the extended chaotic maps switch
Authors: Wang Xiao-Min  , Zhang Jia-Shu  , Zhang Wen-Fang  ,   (1)西南交通大学计算机安全与通信保密研究所，成都  610031; (2)西南交通大学信号与信息处理四川省重点实验室，成都  610031
Published: December 2020

How to design an efficient one-way Hash function is always the hot point in mode rn cryptography researches. In this paper, a Hash function construction method b ased on extended chaotic maps switch is proposed. The extended chaotic model is first built to generate various kinds of chaotic signals at different parts of t he original signals according to the switching schemes, and then chaotic paramet ers of one-way Hash function is modulated by the linear-transformed signals. The advantages of irreversibility, resistance to imitations and sensitivity to init ial values,etc., are also discussed. Simulation results show that this chaotic H ash function based on extended chaotic maps switch has good one-way，weak collis ion property, better security than the chaotic Hash function based on single cha otic map, and it can be realized easily.
Excitation spectra of light from the interaction of highly charged 126Xeq+-ions with solid surface of Ti
Authors: Zhao Yong-Ｔao  , Zhang Xiao-An  , Li Fu-Li  , Xiao Guo-Qing  , Zhan Wen-Long  , Yang Zhi-Hu  ,   (1)西安交通大学应用物理系，西安  710049; (2)西安交通大学应用物理系，西安  710049;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 measurement results on 200—1000nm excitation spectra of light from a solid surface of Ti which is excited by slow highly-charged ions(SHCI) 126Xeq+ （6≤q≤30）with a kinetic energy of 150keV are reported. The results s how that the characteristic spectral lines of the target atoms can be effectivel y excited by the SHCI even though the beam intensity of the incident ions is ver y weak (only about one per one nanosecond). We have also found that when the num ber of the peeled electrons of the projectile is beyond a critical value which d epends on the properties of the target, about 20 for Ti, the spectral intensity of the characteristic spectral lines can be greatly enhanced. Theoretical analys es show that this phenomenon is closely related to the surface plasmon excitatio n of the free electron gas of the metal surface during the potential energy rele ase of the single-electron transfer when the number of the peeled electrons is b eyond the critical value.
PIC simulation of the wake field accelerator driven by multiple-pulse with optim ized intervals
Authors: Xu Han  , Chang Wen-Wei  , Zhuo Hong-Bin  , Yin Yan  ,   国防科学技术大学理学院，长沙  410073
Published: December 2020

The so_called “phase detune”, caused by nonlinear effects which increase the wavelength of the wake wave, when its amplitude exceeds some limitation, is the m ain saturation mechanism of wake waves in multiple pulse laser wake_field accele rator(MP_LWFA). The MP_LWFA with the optimized spacing between the pulses equal to the wavelength of the wake wave, is studied by PIC simulation in this paper. Our simulation indicates that the detuning length and thus the amplitude of the wake wave increases as our expected. Furthermore, the stronger forward Raman sca ttering is stimulated, which plays an important role in stopping the increase of wake waves.
Electron transport properties of MM-HEMT with varied channel indium contents
Authors: Qiu Zhi-Jun  , Jiang Chun-Ping  , Gui Yong-Sheng  , Shu Xiao-Zhou  , Guo Shao-Ling  , Chu Jun-Hao  , Cui Li-Jie  , Zeng Yi-Ping  , Zhu Zhan-Ping  , Wang Bao-Qiang  ,   (1)中国科学院半导体研究所,北京  100083; (2)中国科学院上海技术物理研究所红外物理国家重点实验室, 上海  200083
Published: December 2020

Transport properties of two_dimensional electron gas (2DEG) are crucial to metamorphic high_electron_mobility transistors (MM_HEMT). We have investigated the variations of subband electron mobility and concentration versus temperature from Shubnikov_de Hass oscillations and variable temperature Hall measurements. The results indicate that the electrical performance is the best when the In content is 0.65 in the channel for MM_HEMT. When the In content exceeds 0.65, a large lattice mismatch will cause dislocations and result in the decrease of mobility and the fall of performance in materials and devices.
Structual and optoelectronic properties of polycrystalline silicon thin films p repared by hot-wire chemical vapor deposition at low temperatures
Authors: Wang Liu-Jiu  , Zhu Mei-Fang  , Liu Feng-Zhen  , Liu Jin-Long  , Han Yi-Ｑin  ,   (1)中国科学院研究生院物理系，北京  100039; (2)中国科学院研究生院物理系，北京  100039 ;中国科学院半导体研究所，北京  100083
Published: December 2020

Polycrystalline silicon thin films were prepared by hot-wire chemical vapor deposition (HWCVD) on glass at 250℃，with W or Ta wire as the catalyzers. The structual and optoelectronic properties as functions of the filament temperature, deposition pressure and the filament-substrate distance were studied，and the optimized polycrystalline silicon thin films were obtained with Xc>90% (Xc denotes the crystalline ratio of the film), crystal grain size ab out 30—40nm, Rd≈0.8nm/s, σd about 10-7—10-6 Ω-1cm-1,Ea≈0.5eV and Eopt≤1.3eV.
A study of coupling effect in cellular automata model of traffic flow for two-l ane with open boundary conditions
Authors: Peng Lin  , Tan Hui-Li  , Kong Ling-Jiang  , Liu Mu-Ren  ,   广西师范大学物理与电子科学系，桂林  541004
Published: December 2020

An improved two-lane cellular automaton model for traffic flow was proposed to d escribe the highway traffic under the opening boundary conditions by considering the relative motion of vehicles and the relation of deceleration probability. N umerical simulation have been carried out. The results show the complicated evol ution process of traffic flow. The flow of vehicles can be controlled by the cou pling coefficient b. Different values of b have different effects on the critica l point from free to jam phase.
Study on mechanisms for enhancement kinetics of lasing gases in an optimized sea led-off CO2 laser
Authors: Cheng Cheng  ,   浙江工业大学应用物理系，杭州  310032
Published: December 2020

The kinetics of gases (CO2, N2 and He) in an optimized se aled-off CO2 laser are discussed in details. A comparison of numerical results shows that the po pulation of the laser levels is increased by optimizing the lasing gases, with t he increase of an excited N2 impacting to the upper laser level. Also , decreas ing the electron momentum transition frequency and increasing discharge current result in the increase of the relaxation of the upper rotational laser levels an d the decrease of the level lifetime, thus the lasing saturation intensity in a resonator is increased finally.
The relationship between the resonant wavelength of the long period fiber grati ng and its exposure
Authors: Zhang Dong-Sheng  , Jiang Li  , Zhang Wei-Gang  , Li Li-Jun  , Fan Wan-De  , Yuan Shu-Zhong  , Kai Gui-Yun  , Dong Xiao-Yi  ,   南开大学现代光学研究所,天津  300071
Published: December 2020

In this paper we have derived the Bragg equation of long-period fiber gratings by using interference theory. According to the color centers model and Kramers-Kronig principle, we have studied, theoretically and experimentally, the relationship between the resonant wavelength of the grating and its exposure. The result shows that the resonant wavelength of the long-period fiber grating changes with the UV exposure in the form of the sum of two decaying exponential functions an d the rate of change is controlled by the duty ratio of the mask. The resonant w avelength of the long-period fiber grating is inversely proportional to the duty ratio of the mask.
Calculation and analysis on the wave reflected characteristics of plasma before the conductor plate
Authors: Su Wei-Yi  , Yang Juan  , Wei Kun  , Mao Gen-Wang  , He Hong-Ｑing  ,   西北工业大学航天学院，西安  710072
Published: December 2020

Regarding the nonuniform plasma plate as uniform multilayer slabs, the total wave energy reflectance of the interface between the plasma before a conductor plate and the atmosphere or vacuum can be calculated by applying the equivalent input impedance method. The result obtained is that the reflection characteristics are affected by electron number density, plasma thickness, frequency and transmitting direction of the incident wave. Changing any factor of them, the total wave energy reflectance can be reduced greatly. In the low frequency band, the d istribution of electron number density almost does not affect the reflectance. B ut in the high frequency band, it will affect the reflectance. The effect of pla sma thickness, wave frequency, electron number density distribution on it is alm ost independent of the wave polarizing direction.
Thermal equilibrium of a fluid system on Einstein turntable and its space-time duality
Authors: Li Shuang-Jiu  ,   河北大学物理科学与技术学院,保定 071002
Published: December 2020

The dependence of proper temperature on cylindrical coordinatesT0（ρ）in thermal equilibrium of a fluid system on Einstein turntable is solved by special and general relativity separately. The results show that the contraction of motiontemperature depends only on the speed instead of on the acceleration of subsystems. According to uniformity in space and constancy in time of the coordinate temperature of an equilibrium system, the space-time duality between Einstein turntable and early universe directly presents that the proper temperature of a medium of the early universe is inversely proportional to the spatial scale-factor R(t).
Comparison with solution of convection-diffusion by several difference schemes
Authors: He Wen-Ping  , Feng Guo-Lin  , Dong Wen-Jie  , Li Jian-Ping  ,   (1)国家气候中心，北京 100081; (2)扬州大学物理科学与技术学院，扬州  225009; (3)扬州大学物理科学与技术学院，扬州  225009;中国科学院大气物理研究所，北京 100029; (4)中国科学院大气物理研究所，北京 100029
Published: December 2020

By solving convectiondiffusion equation, we have studied the influence of d if ferent difference schemes on the rumerical solutions under the condition of stoc h astic disturbance of the border or parameter, which provides a reliable differen ce scheme for solving the convectiondiffusion equation, and we have drawn a co nclusion that the influence for the stochastic disturbance on the border or para meter could be controlled by increasing the number of the grid point in numerica l calculation.
The quantum state entropy of Schwarzchild-de Sitter black hole cosmos horizon
Authors: Han Yi-Wen  , Hong Yun  ,   达县师范高等专科学校物理系，达州 635000
Published: December 2020

Using the new equation for density of states due to the generalized uncertainty relation, the entropy of Schwarzchildde Sitter spacetime is discussed. By use of the new equation for density of states, it overcomes the shortcoming that on eliminating divergence the calculation of black hole entropy with brickwall pattern needs a cut off. Thus, it gets the result of the direct proportion betwee n black hole entropy and its horizon area, brings to light the relationship between Schwarzchildde Sitter and its cosmos event horizon and makes clear that the black hole entropy is the entropy of quantum state near the event horizon.
Synchronization of coupled limit-cycle systems
Authors: Zhang Ting-Xian  , Zheng Zhi-Gang  ,   (1)北京师范大学物理系,北京 100875; (2)北京师范大学物理系,北京 100875;曲靖师范学院物理系,曲靖 655000
Published: December 2020

Synchronizations in coupled limitcycle systems are studied. The order parameter does not change monotonically with increasing coupling. Phase synchronization among oscillators shows a treelike bifurcation, and a number of clustered states are experienced. At the onset of synchronization, simultaneous phase slips of all oscillators and quantized phase shifts are observed. The phase synchronization bifurcation is accompanied by a bifurcation process of the amplitudes of oscillators, that is, the synchronization of phases corresponds to an inhomogeneou sprocess of amplitudes.
Prediction of chaotic time series based on fuzzy model
Authors: Wang Hong-Wei  , Ma Guang-Fu  ,   (1)哈尔滨工业大学控制工程系,哈尔滨 150001; (2)青岛海尔技术中心,青岛 266101
Published: December 2020

For dynamic systems with complex, illconditioned, or nonlinear characteristics, the fuzzy model based on fuzzy sets is very useful to describe the properties of the dynamic systems using fuzzy inference rules. Modeling and prediction of nonlinear systems using fuzzy modeling is discussed in this paper. First, the fuzzy space of input variables is partitioned by means of online fuzzy competitive learning. Further, the parameters of fuzzy model are estimated by means of Kalman filtering algorithm. To illustrate the performance of the proposed method, simulations on the chaotic MackeyGlass time series prediction are performed. Combining either offline or online learning with the proposed method, we can show that the chaotic MackeyGlass time series are accurately predicted, and demonstrate the effectiveness.
An adaptive H∞ synchronization approach for continuous-time chaotic systems
Authors: Wei Rong  , Wang Xing-Yu  ,   华东理工大学信息学院，上海 200237
Published: December 2020

An adaptive H∞ synchronization approach for continuoustime chaotic syst ems is proposed. An adaptive controller is designed such that the global asympto tic synchronization between the drive and response systems can be accomplished w ithout noise, and the influence of noises in the response system on the synchron ization error is less than the expected level. Finally, the simulation results v ia Chua's circuit verify the theoretical results.
Synthesis and characterization of three-dimensionally ordered macroporous polystyrene
Authors: Yi Gui-Yun  , Dong Peng  , Wang Xiao-Dong  , Liu Li-Xia  , Chen Sheng-Li  ,   石油大学（北京）重质油国家重点实验室,北京 102200
Published: December 2020

Three-dimensionally ordered macroporous polystyrene was successfully synthesized through using silica sphere colloid crystals as template and in-situ polymeriza tion of styrene inside the template. The silica spheres with a diameter of 330 n m and 2.75% relative standard deviation were prepared by seeding method. For th e purpose of improving the wetting ability between the silica particles and styr ene, the hydrophilic surface of silica particles was switched to hydrophobic by 3-Aminopropyl-triethoxysilan (APS). Three-dimensionally ordered colloidal crystal was prepared by assembling the modified particles through a vertical depositio n technique at 30℃ for 48h. Styrene monomer was filled into the void of the tem plate and the polymerization of the styrene was carried out at 60℃ for 6h, being used (put the initiator in here) as initiator. The three-dimensionally ordered macroporous polystyrene was thus obtained by removing the silica template from polystyrene materials with 04% HF. The macroporous polystyrene shows a beautif ul iridescence in reflected light, which resulted from Bragg diffraction. SEM im ages indicated that the pores with a diameter of about 210nm were arrayed period ically and connected with each other.
Statistical thermodynamics for equilibrium distribution of Au48+—Au52+ in Au plasma
Authors: Zhu Zhi-Yan  , Zhu Zheng-He  , Gao Tao  , Jiang Gang  ,   四川大学原子与分子物理研究所,成都 610065
Published: December 2020

Based on the relativistic multiconfiguration DiracFock theory, the level energies and level degeneration of ions from Au48+ to Au52+have been calculated using the Generalpurpose Relativistic Atomic Structure Progra m with quantum electrodynamics effect and Breit correction. The partition functi on of each ion is derived using statistical thermodynamics. The equilibrium dist ribution of Au48+to Au52+in Au plasma is obtained from the theory of simultaneous reactions.
Theory of ultra-narrow bandwidth optical filter consisting of anomalous dispersion photonic crystal
Authors: Liu Jiang-Tao  , Zhou Yun-Song  , Wang Fu-He  , Gu Ben-Yuan  ,   (1)首都师范大学物理系,北京 100037; (2)中国科学院物理研究所,北京 100080
Published: December 2020

We propose a new theory of ultra-narrow bandwidth optical filter which consists of two-dimensional photonic crystal of an anomalous dispersion material. Based on our investigation of the anomalous dispersion of 6P1/2←6S1/2 tran sition of the cesium atom, we designed a photonic crystal anomalous dispersion o ptical filter (PCADOF) by use of the plane wave expansion method. The calculated result shows that the bandwidth of the filter can be less than 0.002nm.
Interaction between optical vortices carrying opposite topological charges
Authors: Dong Liang-Wei  , Ye Fang-Wei  , Wang Jian-Dong  , Li Yong-Ping  ,   (1)中国科学技术大学物理系,合肥 230026; (2)中国科学技术大学物理系,合肥 230026;中国科学技术大学结构分析开放实验室,合肥 230026
Published: December 2020

The interaction between two optical vortices in a linear medium is investigated numerically. An instability resembling the symmetrybreaking instability occurs when the vortices carry opposite topological charges. The screw dislocations wi ll evolve into another type of dislocationedge dislocation with the propagatin g of optical field. The sum of the topological charges conserves in the whole pr ocess.
Teleportation of quantum states by means of two-mode squeezed vacuum
Authors: Song Tong-Qiang  ,   宁波大学物理系,宁波 315211
Published: December 2020

By means of the expression of twomode squeezed vacuum in electron paramagnetic resonance (EPR) entangled state representation, we study the teleportation of a ny form of singlemode and twomode quantum states by using twomode squeezed vacuum as quantum channels.