bluuebunny/crossref_metadata_2025 huggingface dataset:
THE HIGH PRESSURE MODIFICATION OF LITHIUM POTASSIUM SULPHATE (LiKSO4) AND ITS P-T PHASE DIAGRAM ABOVE ROOM TEMPERATURE
Authors: SHEN ZHONG-YI  , HU JING-ZHU  , ZHANG YUN  , YIN XIU-JUN  ,   中国科学院物理研究所
Published: November 2020

The high pressure transition and phase equilibrium beheviour of lithium potassium sulphate (LiKSO4) were studied by an improved high pressure DTA method and X-ray diffraction in a diamond anvil cell at elevated temperatures. The P-T phase diagram was accurately determined up to 3GPa and 800℃. A high pressure modification of LiKSO4 was observed beyond 1.65 GPa. The structure was determined to be orthorhombic with a = 7.933 ?, b = 9.493 ? and c= 9.679 ?, and its thermal expansion at high pressure and the stability of the quenched sample at normal pressure were also examined.
ON THE EXACT PROOF OF THE METHOD OF INVERSE SCATTERING FOR SOLVING THE EQUATION OF A FERROMAGNETIC CHAIN AND ITS VERIFICATION
Authors: SHUAI ZHI-GANG  , CHEN ZONG-YUN  , HUANG NIAN-NING  ,   (1)暨南大学; (2)武汉大学华中工学院
Published: November 2020

In current deductions of the inverse scattering method for solving the equation of a ferromagnetic chain, the factor λ-1 brings about difficulties. In this note, we show that this factor should be dropped and an equivalent result to the Takhtajan's equation can be obtained, except for some expected corrections at point λ = 0. It is also verified that the solutions given by the ISM satisfy the equation of a ferromagnetic chain.
THE TWO MODE CONVERSION IN AN INHOMOGENEOUS MAGNETIZED PLASMA
Authors: YU WEI  , XU ZHI-ZHAN  , CHEN ZE-ZUN  ,   中国科学院上海光学精密机械研究所
Published: November 2020

The field structures in the overdense region above the resonant paint of an inhomogeneous magnetized plasma are studied. Our work indicates that owing to the mutual conversion be-tween the extraordinary electromagnetic wave and the longitudinal plasma wave, the electromagnetic wave will grow again in the overdense plasma.
STUDY ON A PLANE-LIKE PRECIPITATE IN SILICON SINGLE CRYSTAL BY X-RAY TOPOGRAPHIC METHOD
Authors: CHU XI  , MAI ZHEN-HONG  , DAI DAO-YANG  , CUI SHU-FAN  , GE PEI-WEN  ,   中国科学院物理研究所
Published: November 2020

A plan-like precipitate in silicon single crystal was investigated by means of X-ray section topography. limited topography, dilatation topography and SEM. The configuration and position of the defect in matrix were determined. And a breief analysis about its formation is also presented.
PERCOLATION MODEL OF Ti-Al2O3 CERMET
Authors: NAN CE-WEN  , CHEN XIN-ZHENG  ,   (1)轻工业部上海玻璃与搪瓷研究所; (2)武汉工业大学硅酸盐材料科学与工程系
Published: November 2020

The relation between the microstructure and the macroscopic conductivity of Ti-Al2O3 cermet is analysed by using percolation theory. It is found that the result of percolation model is consistent with experimental result. The percolation threshold ω* the critical percent content of Ti-Al2O3 cermet is 0.16, and critical exponents are the same as those of three-dimensional continuous percolation.
EXPERIMENTAL STUDIES ON LOW TEMPERATURE MAGNETISM OF THE Gd3Ga5-xAlxO12 SINGLE CRYSTAL
Authors: LlU PIN-QING  ,   中国科学院低温技术实验中心
Published: November 2020

Gd3Ga5-xAlxO12 single crystal has been grown by the Czochralski rechnique. It was ascertained as garent single phase material by X-ray photography. Experimental studies of the magnetization and susceptibility of Gd3Ga5-xAlxO12 have been carried out along the [111] crystal axis in the temperature range of 1.5 to 77 K, and compared with Gd3Ga5O12 (GGG).The primary results show that the susceptibility of this material obeys the Curie-Weiss law when the magnetic field is below 500(Oe), the ordering temperature is far below 1.5 K. The magnetization of GGAG is about 4% higher than that of GGG for magnetic fields greater than l0000(Oe). When the magnetic field is about 30000 (Oe). The Critical magnetic field of GGAG is about 4000(Oe) higher than that of GGG. It is shown that the substitution technique is efficient in searching after new working substance for magnetic refrigerator.
COLLISION CROSS SECTIONS AND TRANSPORT COEFFICIENTS IN AN INDUCTIVELY COUPLED ARGON PLASMA
Authors: HUANG MAO  , LIU KE-LING  ,   (1)北京大学分校物理系; (2)中国科学院化工冶金研究所
Published: November 2020

Collision cross sections as well as electrical conductivity, thermal conductivity, diffusion coefficients and viscosity coefficients of an inductively coupled argon plasma are calculated. The results indicate that thermal conduction process plays an important role in energy transfer, while ambipolar diffusion leads to a much higher electron density in the cool plasma regions as compared with the value predicted by local thermal equilibrium. More significantly, both three body recombination and superelastic collision give rise to the creation of a large number of energetic electrons in the cool plasma regions. Such a deviation of electron velocity distribution from a Maxwellian may have a special significance for excitation mechanism of the plasma used as an emission spectroscopic source.
STUDY OF THE DEFECTS IN OXYGEN PLASMA IRRADIATED n/n+ Si
Authors: WANG FANG-PING  , XU JIAN-GUO  , SUN HENG-HUI  ,   复旦大学物理系
Published: November 2020

The defects in oxygen plasma irradiated Si have been studied. It is found that two kinds of defects E1(Ec-0.46 eV) and E2 (Ec-0.04 eV) are generated in the sample. The deep level optical spectroscopy reveals that defects E2 has a strong electron-phonon coupling, its Frank-Condon shift is 0.76 eV. For E1, the coupling is weaker, its Frank-Condon shift is 0.04 eV. The analysis shows that the phonon modes coupling to defects E1 and E2 is 28.7 meV and 20 meV respectively.
VACUUM ULTRAVIOLET SPECTRA OF CT-6B TOKAMAK PLASMA
Authors: WANG WEN-SHU  , LI ZAN-LIANG  , HUANG MAO  ,   (1)北京大学分校物理系; (2)中国科学院物理研究所
Published: November 2020

A spectrographic survey of the impurity lines was made on the CT-6B Tokamak with I metre grazing incidence spectrograph. The observed wavelength ranges were from 1580 to 550 ? and from 460 to 43 ?, using 300 lines/mm and 1200 lines/mm gratings respecrively. The survey revealed that the main impurities in CT-6B Tokamak plasma are Mo for high Z impurities and C, N, O for low Z impurities. There are a large number of OV and OVI lines with intense emission. We also observed MoVIIl resonance lines 234.314 ?, 235.510 ? and 237.215 ?. The shortest observed wavelengths are the second order of OVII lines 21.6020 ? and 21804 ?. The first order of these two lines situate beyond the film and can not be recorded. According tc the features of the spectra and the ionization potentials of OV, OVI as well as MoVII, the average electron temperature for CT-6B Tokamak is estimated to be about 140 eV. Oxygen is the main impurity in CT-6B Tokamak, and its lines emission is the main portion of energy loss in CT-6B Tokamak. Lines of the main components of the vacuum-vessel material such as Fe, Cr, Ni and Ti have not been found.
TRANSMISSION PROBABILITY AND RESONANCES IN NON-SYMMETRIC ONE-DIMENSIONAL MICROSCOPIC NORMAL METAL RING
Authors: CHEN GENG-HUA  , ZHAO ZHONG-XIAN  ,   中国科学院物理研究所
Published: November 2020

Basing on the method of Büttiker et al., the analytic expressions of low temperature transmission amplitude for two kinds of normal metal ring with non-symmetric branches are obtained. The interesting resonances in the transmission probability for such structures are discussed. The results derived from the general analytic expression in two special limits are similar to those in reference [11] . In addition, we point out that there are some mistakes in equations (4.24) and (4.39) of reference [11] .
THE STEP-RELATED ELECTRONIC STATES ON THE VICINAL SURFACES OF Si(001)
Authors: CHEN XIAO-HUA  , XU YA-BO  , W. RANKE  , LI HAI-YANG  , JI ZHEN-GUO  ,   (1)Fritz-Haber-Institut der MPG,F. R. G.; (2)浙江大学物理系; (3)浙江大学中心实验室
Published: November 2020

Angle-resolved ultraviolet photoelectron spectroscopy has been used to investigate the step-related electronic states on the vicinal surfaces of Si(00l). Such states have been found at 0.5-0.6 eV below EF at Γ point (K = 0) for vicinal surfaces with steps along 〈100〉 or 〈110〉. The dispersion of these states is smaller than that of the (001) surface states.
THE EFFECT OF ANNEALING ON THE PROPERTIES OF AMORPHOUS GERMANIUM/CRYSTALLINE SILVER BILAYER
Authors: LIU HONG-BAO  , WANG JI-HONG  , WANG CHANG-SUI  , XUE BAI  , ZHANG YU-HENG  ,   中国科学技术大学物理系
Published: November 2020

By using X-ray differaction, SEM and the measurement of sheet resistance, the effect of annealing of a-Ge/c-Ag bilayer were studied. Sheet resistance of the bilayers were measured in the range 80-300 K. The relation between sheet resistance at room temperature and annealing temperature was presented. A new diffusion mechanism was found. As the temperature increased, amorphous germanium crystallize. In the meantime, a part of Ge diffuse into Ag. When the temperature went on increasing, the germanium which diffused into silver would separate out again. The activation energy of diffusion was estimated to be 0.15 eV by means of measuring the sheet resistance of bilayer.
NEW C-V CHARACTERISTIC OF Si pn DIODES PREPARED BY MOLECULAR BEAM EPITAXY
Authors: PENG CHENG  , SHENG CHI  , SUN HENG-HUI  ,   复旦大学物理系
Published: November 2020

The C-V characteristic of a silicon p-n diode grown by molecular beam epitaxy (MBE) technique was carefully studied in the case that the space charge region reached the edge of MBE layer. Based on the theoretical analysis and experimental measurement, the impurity concentration in unintentionally doped n-type MBE layer was determined to be 8.0×1014cm-3. This method is shown to be a new way to find out impurity concentrations in supper-thin semiconductor layers.
THERMOMAGNETIC EFFECT OF THE Sm-T(T = Fe, Co ) AMORPHOUS THIN FILMS IN HIGH FIELDS
Authors: FANG RUI-YI  , DAI DAO-SHENG  , RAO XIAO-LEI  , LIU ZUN-XIAO  , LAN JIAN  , WAN HONG  ,   北京大学物理系
Published: November 2020

The temperature dependence of magnetization at H=0.1-7T for amorphous SmxT1-x (T = Fe, Co) thin films was investigated in the range of 1.5 to 300 K. It was found that there was a maximum magnetization in the σ(T) curves, measured in the temperature rising process, for the SmxCo1-x thin films (x=0.46, 0.48, 0.54, 0.65). For the Sm-Co alloys, the temperatures, corresponding to σmax, are about 25-28 K and are independent of the composition. But the Sm-Fe amorphous alloys are different from the Sm-Co alloys, in the former the temperature corresponding to σmax depends on both the field and the composition of the alloys. In addition, it was found that there was σmin (or a repaid variation) at T≈6 K, and σ(T) decreased very slowly near room temperature. It was suggested that the thermomagnetic effect for the Sm-Co thin films at high field may be caused by the contribution of Sm moment to the magnetization, though the magnetic moment of Sm atoms is very small (≈0.1μB), and the random local anisotropy is strong at low temperatures and changes signicantly between 20-30 K. But the thermomagnetic effect of the Sm-Fe amorphous alloys may be caused by the dispersion of the Fe moments. The σmin at T≈6 K and the slow decrease of σ(T) near room temperature may be caused by fluctuation of composition in these alloys.
THE THEORY OF ULTRASONIC ATTENUATION IN SUPERIONIC GLASSES
Authors: WANG YANG-PU  , JIN QI-SHU  ,   苏州大学物理系
Published: November 2020

According to IRD theory, we considered the infrared divergence response in the supe-rionic glasses, resulting from mang-body interactions caused by the presense of disorder. On the basis of studying a new relaxation mechanism, we revised the rate equation of anelasric strain, and then using Boltzmann superposition principle, the formula of ultrasonic attenuation with IRD is derived. From this, the power law dependence of ultrasonic attenuation on frequency α∝ωn at low temperature side and an apparent activaion energy EA+ are obtained. They are in agreement with experimental data for superionic glasses (Agl)x(Ag2O·nB2O3)1-x.
EFFECTIVE ELASTIC CONSTANT OF THE SEMICONDUCTOR SUPERLATTICE
Authors: XIONG XIAO-MING  , TAO RUI-BAO  ,   复旦大学物理系
Published: November 2020

The effective elastic constant of the GaAs-GaAlAs kind semiconductor superlattice has been obtained by means of the mathod of Green's function in the long Wave approximation. The results show that the effective elastic constant is not greater than that of either kind of the matter which are the components of the superlattice. In the limit of b = 0 and b = a, where a is the period of the superlattice and b is the width of one of the component, the te-sult reduces to the elastic constant of one single medium.
HALF WAVELENGTH AND STOPPING POWER FOR PLANAR CHANNELED 4He+ IONS IN Al AND Si CRYSTALS
Authors: JIN WEI-GUO  , ZHAO GUO-QING  ,   复旦大学原子核科学系
Published: November 2020

Using a detection system with high resolution, backscattering spectra for 1-2 MeV 4He+ incident along Al (100) and Si(l00) and (110) planes are measured at a variety of entrance (θin) and exit (θout) angles. The energy intervals between the peaks in the energy spectra are plotted as a function of cosθin/cosθout Half wavelength and stopping power for 1-2 MeV 4He+ in these three channeling planes are obtained. The experimental half wavelength is in agreement with the calculated value within the limit of error and the planar channeled stopping power is slightly greater than the random stopping power.
THE INFLUENCE OF Pt AND Pd ON SURFACE ENHANCED RAMAN SCATTERING OF PYRIDINE ON Ag SURFACE
Authors: PU XIAO-YUN  , WANG ZHONG-YONG  , MO YU-JUN  , WANG RUI-LAN  , LI HONG-CHENG  ,   (1)云南大学物理系; (2)中国科学院物理研究所
Published: November 2020

We measured SERS intensities of pyridine on Pt and Pd deposited as overlayers on several silver island films, obtained the damping curve of SERS intensities versus Pt and Pd thickness. The results were compared with the electromagnetic damping theory proposed by Murray. We concluded that the short range damping play a very important role. Moreove, a new mode related to Pt and Pd overlayers were also discovered.
POSSIBILITY OF BIPOLARONIC EXPLANATION FOR HIGH TEMPERATURE SUPERCONDUCTING TERNARY METAL OXIDE
Authors: DING SHANG-WU  , HOU LEI  ,   中国科学院武汉物理研究所
Published: November 2020

Through analysing the condition of the formation of bipolarons, we point out that the bipolaronic explanation for high temperature superconducting ternary metal oxide, given by Ref. [1] is doubtful.
SPACE DISTRIBUTION OF HIGH IONIZING IONS IN PLASMA
Authors: FENG XIAN-PING  , XU ZHI-ZHAN  , JIANG ZHI-MING  , ZHANG ZHENG-QUAN  , CHEN SHI-SHENG  , FAN PIN-ZHONG  , TIAN LI  , ZHOU ZI-JIN  ,   中国科学院上海光学精密机械研究所
Published: November 2020

Using X-ray crystal spectrograph, light probing and X-ray pin-hole camera, we have measured the distributions of high and low ionizing ions of plasma in the three-dimensional space. We have found the spaces in which the high and low ionizing ions occupied were of conical forms, but overlapped each other and the directions of the cones were opposite. in addition, we have also obtained two distrbutions of ion densities.
SELECTIVE PHOTODISSOCIATION OF AMMONIA AT 000 AND 201 BANDS
Authors: XIE XIAO-XIANG  , J. BIESNER  , K. H. WELGE  ,   (1)联邦德国Bielefeld大学物理系; (2)中国科学院安徽光学精密机械研究所
Published: November 2020

The photofragnentation dynamics of ammonia molecules following pulsed UV laser excitation of ground state to the two lowest levels ν′2 = 0 and 1 (ν2 vibrational mode) of their ?1(A"2) electronic excited state has been investigated by monitoring thetime-of-flight spectra of the nascent H-atom products. The spectra confirm recent revised estimates of the quantity D00(H-NH2) = 4.645 eV and reveals that the majority of the accompanying NH2 (X2B1) fragments are formed vibrationally unexcited, but with high levels of rotational excitation specifically concentrated about the a-inertial axis. The NH2(X) fragments resulting from photodissociation via the ν′2 = 1 level of NH3(?) carry a higher level of internal excitation and show an inverted population distribution over the N = Ka rotational levels.
CONDUCTANCE OF HIGH-VALENCE IONS IN MONTMORILLONITE SOLID ELECTROLYTES
Authors: ZHU BIN  , WANG DA-ZHI  , YU WEN-HAI  ,   中国科学技术大学
Published: November 2020

Conductance of high-valence ions in montmorillonite solid electrolyte was investigated with various chemical and physical ways, in particular, by the methods of electrical property measurment and electrochemistry. The results show that montmorillonite is a practical and promising solid electrolyte material. Some mechanisms on migration for high-valence ions in montmorillonite are discussed.
GENERALIZED VILLAIN ANALYSIS FOR U(1) MODEL WITH AN EXTENDED LATTICE ACTION
Authors: XU ZAI-XIN  , ZHU BEN-YUAN  ,   华东师范大学物理系
Published: November 2020

A generalized Villain formula is introduced. In this general Gaussian approximation, the topological properties of the electromagnetic loop for compact QED in four dimensions with an action which is the admixture of two terms with any different periodicities are investigated. The common properties of the phase structure, including two kinds of different partial confinement phases and a two-photon phase, of this model in the whole parameter space are discussed. By using the modified Migdal-Kadanoff group transformation, the phase diagrams for the cases of (N1, N2) = (l,5), (1,6), (1,7) are obtained. The numerical results are consistent with the theoretical analysis.
PHOT OREFLECTANCE SPECTROSCOPY OF GaAs DOPING SUPERLATTICES
Authors: TANG YIN-SHENG  , WANG BENG-SHEN  , JIANG DE-SHENG  , ZHUANG WEI-HUA  , LIANG JI-BEN  ,   (1)中国科学技术大学; (2)中国科学院半导体研究所
Published: November 2020

Room temperature photoreflectances of a MBE GaAs doping superlattice were measured under different pump beam intensities. A series of fine structures corresponding to forbidden transitions (△n≠0) were observed af lower pump beam intensities. This means it is net a third derivative spectrum. A first derivative lineshape of photoreflectance for doping super-lattices was suggested, and the modulation mechnism was discussed. Theorefical calculations give a good explanation to the experiments.
OPTICAL PROPERTIES OF THE a-Si:H/a-SiNx:H SUPERLATTICE FILMS
Authors: WANG ZHI-CHAO  , LIU XIANG-NA  , FENG XIAO-MIE  , GENG XI-SHENG  ,   南京大学物理系
Published: November 2020

In this paper, the optical absorption coefficient, optical gap and the index of refraction of a-Si:H/a-SiNx:H superlattice films were studied as a function of a-Si:H sublayer thickness with a-SiNx:H sublayer thickness being kept constant.
ATOMIC MANY-BODY CALCULATIONS ON THE GROUND STATE EXCHANGE-CORRELATION ENERGY OF BERYLLIUM ATOM
Authors: LIU TONG-JIANG  , ZHANG ZHI-JIE  , ZHAO YI-JUN  ,   长沙工学院应用物理系
Published: November 2020

Up to now, almost all many-body theoretical calculations on the ground state of atoms took the Hartree-Fock (HF) model as zeroth order approximation. In this paper, zeroth order Hamiltonian is taken to be Hartree-Fock-Slater (HFS) type, in the double excitation approximation, many-body calculation on the ground state exchangecorrelation energy of beryllium atom is made, the result is in good agreement with experiments and other many-body theoretical calculations, which take HF model as zeroth order approximation. Our calculation shows that, take the HFS model as zeroth order approximation instead, successful many-body calculation on the ground state property of closed shell atoms can also be made.
A STUDY ON THEORETICAL HABIT OF KTiOPO4 CRYSTAL
Authors: LIU XIANG-YANG  , JIANG MIN-HUA  , SHAO ZONG-SHU  ,   (1)山东大学晶体材料研究所; (2)中国科学院福建物质结构研究所
Published: November 2020

In order to solve the problems on calculation of attachment energy Eatt of ionic crystals with complicated structures, several formulas derived according to the principle of PBC (Periodic Bond Chain) theory is presented. The appropriate computing programme has been worked out. The morphology of KTiOPO4 was deduced from the structure. The categories of the crystals faces have been distinguished by means of PBC theory. It was found that {100}, {011} are F-forms, and {210}, {010} are more important S-forms. The form of {001} is found to be K face. The calculation of Eatt for each form has been carried out, and it gives the relative importance of these faces. The results are in satisfactory agreement with observations. The calculating formulas and the programs can be used directly for calculating Eatt of other crystals belong to cubic, tetragonal and orthorhombic systems.
THE GENERALIZED DYNAMICAL EQUATION OF OPTICAL BISTABILITY AND LASER AND ITS STABILITY ANALYSIS
Authors: OU FA  , CAI YONG-QIANG  ,   华南工学院物理系
Published: November 2020

A single-mode dynamical equation is obtained from the Maxwell equation with the slowly varying amplitude approximation and the boundary conditions of the cavity, here the mean field limir and the good quality cavity case have been used. This equation is useful in describing the dynamical behavior of intrinsic optical bistable systems and/or lasers with injected sig-nals for any kinds of materials including two-level atoms. Furthermore, according to the li-near stability analysis, a generalized instability criterion is derived.
ELECTRONIC TRANSPORT PROPERTIES OF HIGH CONDUCTIVITY a-Si:H:Y ALLOY
Authors: CHENG XING-KUI  , ZHAO WEN-JIN  , DAI GUO-CAI  ,   山东大学物理系
Published: November 2020

The high conductivity a-Si:H:Y alloy films prepared by rf sputtering have been obtained. The room temperature d.c. conductivity is about 2×101 Ω-1·cm-1 as Y doping concentration reaches 20 at %. Measurements showed that the alloy films are of n-type. The plots of In a versus 1/T over temperature range investigated can be fitted by two straight lines with a kink occurring at a temperature which is ～70℃, ～75℃ and ～90℃, respectively, for samples deposited at substrate temperature T2 = 260℃, 290℃ and 330℃. Present results may be explained on the assumption that there are two parallel transport paths, one above kink temperature takes place in the conduction band and another below kink temperature in the Y-rela-ted donor impurity band, Moreover, we estimated that the center of the impurity band lies about 0.06-0.07 eV below the conduction band EC.
7Li NMR INVESTIGATIONS DURING PER-CRYSTALLIZATION PROCESS IN AMORPHOUS IONIC CONDUCTOR B2O3- 0.7Li2O-0.7LiCl-xAl2O3
Authors: SU FANG  ,   中国科学技术大学基础物理中心
Published: November 2020

To avoid absorbing moisture from the air, we have sealed all samples in high vacuum, and performed 7Li NMR investigations during pre-crystallization process of amorphous ionic conductor B2O3-0.7Li2O-0.7LiCl-xAl2O3(x = 0.15, 0.10 and 0.05) at 293 K and 77 K. We find that there is only spin-spin relaxation time of lithium ions in solid phase, T2= 87μs, which obeys Gaussian decay law at 77 K. At. room temperature all lithium ions devide into two phases. T2s of lithium ions in solid phase still obeys Gaussian law of decay, T2s =127 μs, but T2l of lithium ions in liquid phase obeys Lorentzian law. For three amorphous lithium-ionic conductor B2O3-0.7Li2O-0.7LiCl-xAl2O3 (x = 0.15, 0.10 and 0.05), T2l of lithium ions in liquid phase increases rapidly, i.e. their width of 7Li NMR absorption line becomes much narrower at about 401°,388°and 381℃ respectively. Hence the physical picture of interfacial effect between amorphous matrix and the crystallites is again confirmed.
SPONTANEOUS EMISSION OF AN ATOM NEAR THE SURFACE OF A SUPERLATTICE FILM WITH PERIODIC OR QUASI-PERIODIC STRUCTURE
Authors: LI XIAO-SHEN  , GONG CHANG-DE  ,   (1)南京大学物理系; (2)中国高等科学技术中心(世界实验室)理论物理中心,南京大学物理系
Published: November 2020

The surface-dressed optical Bloch equations and the Maxwell equations are combined consistently to obtain spontaneous decay rates and frequency shifts for an atom near the surface of a superlattice film with periodic or quasi-periodic structure. The effects of the number, thickness and dielectric properties of the layers constructing this film on the spontaneous emission properties are discussed. The results for the two different cases of periodic structure and quasi periodic structure are comparable.
STUDY OF SCATTERING OF PLANE WAVE THROUGH DISCRETE RANDOM MEDIUM BY DIRECT ANALOGUE AND STATISTICAL ESTIMATION
Authors: WU ZHEN-SEN  , WANG YI-PING  ,   西北电讯工程学院物理系
Published: November 2020

In this paper, starting from transport theory, estimated functions of Monte carlo direct analogue and statistical estimation have been obtained by means of term wise integration. We deal with variations of transmissivity and reflectivity in optical thickness τ, albedo of a single partical a, and anisotropy g when plane wave passes through a layer discrete random media. The results of statistical estimation method are in good agreement with those given in reference [2]. As a result of considerable statistical fluctuation of scattering point samples in direct analogue method, the deviation of calculation would be larger as the optical thickness increases or anisotropic scattering or absorption becomes stronger.
TEMPERATURE DEPENDENCE OF THE ELECTRICAL RESISTIVITY FOR AMORPHOUS FeZrB ALLOYS
Authors: SHEN BAO-GEN  , ZHAN WEN-SHAN  , ZHAO JIAN-GAO  , CHEN QING-HUA  , CHEN JIN-CHANG  ,   (1)北京师范学院物理系; (2)云南大学物理系; (3)中国科学院物理研究所
Published: November 2020

The electrical resistivity of amorphous (Fe1-xZrx)84.5B15.5 (X=0, 0.02, 0.04, 0.06, 0.08, 0.1 and 0.15) and Fe90-xBxZr10 (X = 0, 4, 10, 16 and 20) alloys has been studied as a functiom of temperature in the range of 300 to ≈950 K. We find that, for the samples with X = 0.02 to X = 0.08, the curves of ρ(T)/ρ(300 K) vs T have two linear slopes and the turning point appears above curie temperature Tc. The temperature coefficients α1 of the electrical resistivity at Tc decrease with the increase of Zr content. Above 8 at% Zr, ρ(T)/ρ(300 K)-T curves of the all samples show negative temperature coefficients and a minimum near Tc. Finally, the composition dependence of the minimum temperature Tmin and the temperature coefficients α of resistivity are discussed in brief.
POLARIZATION EFFECT OF LIGHT IN DIAMETER MEAS UREMENT BY DIFFRACTION METHOD
Authors: BAI GUI-RU  , LU HONG-JUN  , XING XIAO-ZHENG  ,   中国科学技术大学物理系
Published: November 2020

In this paper, formulas of electromagnetic field diffraction on a metal filament are given. We report the experimental and calculated results of diffraction of linear polarized light on a metal slit and its complemencary diffracting screen of filament. The polarization effect in diameter measuremenr of filament by diffraction method is presented quantitatively. Calculated results agree with experimental results.
CONDUCTIVITY IN THE DISORDERED LAYER SYSTEM
Authors: JIANG QI  , GONG CHANG-DE  ,   南京大学理论物理中心物理系
Published: November 2020

In this paper, the crossover effect of the dimensionality in the disordered layer system is studied by using the post-CPA method for the vertex. The effective dimensionality of the system is determined by the interlayer coupling t. It is shown that Anderson transition will occur at the critical value tc. Boltzmann conductivity, the dynamical conductivity corresponding to the maximum crossed diagrams, the d. c. conductivity and the localization length near the critical point are calculated.
THE PROXIMITY EFFECT AND MUTUAL DIFFUSION IN a-Ge/Ag LAYERS
Authors: ZHANG YU-HENG  , LIU HONG-BAO  ,   中国科学技术大学物理系
Published: November 2020

In the present work, the behaviors of a-Ge/Ag composite layers are studied. These layers are composed of amorphous Ge film with thickness 2000 ? and Ag film with different thickness. It is found that, when the thickness of Ag film decreases, the electrical resistivity of the composite layer at room temperature becomes more and more smaller than that of Ag mono-layer with the same thickness. The proximity effect at room temperature is shown clearly by experiment. As the samples are annealed, we obtain various R(Ta)-T relations under different annealling temperature Ta and various dependences of R300k on Ta for layers withe different thickness of Ag film. Based on structural analysis by XRD and composition analysis by EMP, and observation with TEM and SEM, the new phenomena are explained.
X-RAY MEASUREMENTS ABOUT STACKING FAULTS IN DEFORMED ALPHA BRASS
Authors: TENG FENG-EN  , WANG YU-MING  ,   吉林大学材料科学研究所
Published: November 2020

The probabilities α′,α″ and β of intrinsic, extrinsic and twin stacking faults were measured respectively based on previous determination of Deff, ρ, M, Re and of samples A, B, C. The stacking fault energy γ and true subgrain size D0 were also obtained.
THE DIFFRACTION INTENSITIES OF INCOMPLETELY POLED FERROELECTRIC CRYSTALS
Authors: ZHONG WEI-LIE  ,   山东大学物理系
Published: November 2020

Incomplete poling of ferroelectric crystals has significant effect on their diffraction intensities. In the crystal structure determination, this effect must be taken into account. For lead hydrogen phosphate, appropriate equations are derived to correct this effect. Incorporating this correction in the structure determination of this crystal, a better fit is obtained.
NONEQUILIBRIUM PHONON EFFECTS IN HOT CARRIER RELAXATION PROCESSES OF MULTIPLE QUANTUM WELL STRUCTURES
Authors: LI YU-ZHANG  , XU ZHONG-YING  , GE WEI-KUN  , XU JI-SONG  , ZHENG BAO-ZHEN  , ZHUANG WEI-HUA  ,   中国科学院半导体研究所
Published: November 2020

Considering the phonon absorption and the phonon emission, we solve the equation for average energy loss rate of carriers and the hot phonon Boltzmann equation. We find that τavg is a sum of the electron phonon interaction time constant and the nonequilibrium phonon. decay time.
GAP STATES DUE TO INTRINSIC DEFECTS IN a-Si:H
Authors: ZHANG RUI-QIN  , DAI GUO-CAI  , GUAN DA-REN  , CAI ZHENG-TING  ,   (1)山东大学理论化学研究室; (2)山东大学物理系
Published: November 2020

Calculations of electronic structures for Si29 and Si47 clusters, which are cut from continuous random networks of a-Si, and those of simple ones Si8H18,Si17, have been performed by using CNDO LCAO MO method. The origin and nature of the gap states due to intrinsic defects such as weak bond, bent bond and charged configurations are examined in a-Si:H. The results show that two weak bond states situated in both sides of band gap have been contracted and shifted to the center of the gap as the weak bond is stretched. These weak bond levels have been shifted to some location near the top of valence band or near the bottom of conduction band due to extra charges. The bent bond states mainly appear near the top of valence band. When the bond is bent severely,the bond level shifted upwards, close to the center of band gap from below. The structural lopological disorder may induce the gap states at any position within the band gap. It is suggested that all the weak bond and bent bond as well as charged configuration are the principal forms of intrinsic defects in a-Si:H. Various experimental results of gap states are explained according to these theoretical calculations.
A DISCRETE ELASTIC APPROACH FOR THE SELF-ENERGY OF THE CRYSTALLINE DISLOCATION
Authors: SUN ZONG-QI  , ZHU SHI-XUE  ,   中国科学院金属研究所
Published: November 2020

As the discrete lattice structure of crystal is considered, it is easy to see that slip can only take place between atoms, thus no atom is situated at the centre of dislocation exactly, the discrete elastic energy belongs to each atom near the centre of dislocation is limited everywhere. Under the assumption of rigid dislocation, using the analytical results of the elastic theory for dislocations directly, the inner cut radius of a singular crystalline dislocation and its periodic variation along with the position of dislocation centre are obtained. For the case of singular screw dislocation in simple orthogonal crystal, the first order approximation coincides with the result of Peierls model. The self energies and effective inner cut radii for two kinds of crystalline system (fcc and bcc) are calculated, and the effect of anisotropic elasticity is taken into account primarily.It is shown that the slip plane for a dislocation is not a geometric plane. The slip plane for the screw dislocation in bcc crystal looks like a bee nest.The possibility to further estimate some second ary effects by this discrete elasticity approach is pointed out.
SIZE EFFECT IN THE FILM OF n-VECTOR MODEL
Authors: ZOU NAN-ZHI  , GONG CHANG-DE  ,   (1)南京大学物理系理论物理中心; (2)中山大学物理系材料科学研究所
Published: November 2020

We have studied the size effect in the film of n-vector model with periodic boundary by using field theoretical method. It is found that when the system dimension satisfies the condition d>, the size effect takes the Fisher's scaling form, in other cases, no-scaling can be defined. Further more we have also discussed the dimensional crossover phenomena and state equation.
EXPERIMENTAL INVESTIGATION ON PROPERTIES OF E. C. H. PLASMA AND HOT ELECTRON RING
Authors: GUAN WEI-SHU  , WANG EN-YAO  , CHENG SHI-QING  , DUAN SHU-YUN  , WANG JI-HAI  , GU BIAO  , SHANG ZHEN-KUI  ,   中国西南物理研究所
Published: November 2020

The ECRH experiment has been carried out on a simple mirror-MM-2 device by use of a 15 GHz high power gyrotron. The experimental results showed that the preionization time will be rapidly shorten following raising the pressure of puffed gas. Duing the "C-mode" operation where the gas pressure is higher, the radial profile of plasma density exhibits a saddle shape. The gas "pressure window" for building a hot electron ring is (0.4-1.2)×10-5 Torr, as the gyrotron output is about 30 kW. Simply by using a movable Langmuire probe accompanied with diamagnetic measurment. it has been determined that the hot electron ring radius is 7 cm, the thickness is about 4 cm and the axial boundary of the ring extends from Z= ±10 cm to Z=±20cm, when the central field is 2.95kg. The hot electron temperature is 140 to 170 keV. The average beta value of hot electron ring is (4-5)%. The radial bursts of electrons due to ring instabilities accompanied with the drops of the diamagnetic signal have also been observed.
PROBE DIAGNOSTICS OF THE ELECTRON ENERGY DISTRIBUTION FUNCTION IN A LOW PRESSURE RF PLASMA
Authors: ZHU WEN-HAO  , ZHU NAN-QIANG  , CHEN YUE-SHAN  ,   清华大学工程力学系
Published: November 2020

A measuring system is developed for diagnostics of the electron energy distribution function (EEDF) in a electrodeless low pressure rf discharge with a triple-probe system by using the probe-current modulation method. The EEDF of a nitrogen plasma in the pressure range of 10-3-10-1 Torr are obtained. The effect of rf voltage penetrating the probe sheath on the determination of the EEDF is studied both theoretically and experimentally. A new approach used to estimate the value of rf voltage in the probe sheath and to calculate the actual EED from distorted distribution recorded during experiments is presented and the experimental results are corrected by using the proposed method to obtain the true EEDF. The difference between average electron energy calculated from corrected EED and that calculated from the V-I characteristics of the probe is slight, being not greater than 5%, this result seems to give indirect evidence in favor of the procedure used to determine the actual EED and the reliability of the measuring system.
A SIMPLE THEORY FOR UNDERSTANDING THE REGULARI- TY OF CHEMISORPTION ENERGY OF SIMPLE GASES ON TRANSITION METALS
Authors: FAN XI-QING  , SHEN SAN-GUO  , ZHANG DE-XUAN  ,   郑州大学物理系
Published: November 2020

We presented a method for calculating the chemisorption energy of simple gases on transition metals series. The simplified d-band model of Allan has been applied to describe the electronic structure of transition metal surface, and the chemisorption energy is calculated by making use of the generalized phase shifts. The method is employed to study the adsorption of hydrogen and oxygen on 3d and 4d transition metals. The calculated results of the chemisorption energies show remarkable systematic trends, in good agreement with experiment. The calculated adsorbate induced electronic energy level [also being referred to as the split-off energy] is at approximately 6 eV below Fermi energy, that is comparable to UPS experiments. The conclusion deduced from the calculation is as follows: the difference between the Fermi level and effective adsorbed energy level (EF-εa.) plays the crucial role in determining the trends in the chemisorption energy, the variation in the bandwidth across the series and the adatom-metal atom transfer matrix element ν are of secondary importance.
A STUDY OF COVER-DEPOSITION CHROMIUM ON DIAMOND AND GRAPHITE SINGLE CRYSTAL SURFACES
Authors: GAO QIAO-JUN  , WANG SHENG-QIANG  , LIN TING  , HU YI-FEI  , LIN ZENG-DONG  ,   (1)北京大学物理系,北京,100871; (2)北京市粉末冶金研究所,北京,100075
Published: November 2020

The cover-deposition chromium on diamond and graphite single crystal surfaces using X-ray and electron diffraction structure analysis technique have been studied. Under the condition of vacuum of 10-5 to 10-6 torr and the temperature higher than 900℃ while the small grain diamonds or highly oriented graphite platelets hid in electrolytic chromium powder, the Cr3C2 and Cr7C3 can be epitaxially grown on diamond or graphite surfaces. In this paper, we discuss the growth condition of chromium carbide and the physical mechanism of cover-deposition epitaxial growth.
PHASE-LOCKED EPITAXY OF Ge/Si SUPERLATTICES BY USING RHEED INTENSITY OSCILLATIONS
Authors: CHEN KE-MING  , JIN GAO-LONG  , SHENG CHI  , ZHOU GUO-LIANG  , JIANG WEI-DONG  , ZHANG XIANG-JIU  , YU MING-REN  ,   复旦大学表面物理实验室,上海,200433
Published: November 2020

Reflection High Energy Electron Diffraction (RHEED) intensity oscillations during the growth of alternating Ge and Si layers were observed, and the growth behavior during molecular beam epitaxy of Ge/Si ultra-thin multi-layered structures on Si(l00) and Si(lll) substrates has been studied. By using RHEED intensity oscillation, we have fabricated the Ge(2ML)/Si(2ML) and Ge(4ML)/Si(4ML) ultra-thin superlattices by phase-locking method.
SPIN WAVE SPECTRUM IN HEISENBERG ANTIFERRO-MAGNETIC SUPERLATTICES
Authors: ZHONG JIAN  ,   东南大学物理系,南京,210018
Published: November 2020

By means of linearized Holstein-Primakoff transformation and Green function theory, the spin wave dispersion curves are obtained for superlattices consisting of two kinds of Heisenberg antiferromagnetic layers. It is interesting that the results are different in cases that a super-cell contains odd or even number of atomic planes, implying differences in physical properties.
COLLISION-INDUCED DISSOCIATION (CID) (Ⅰ)——TIME-DEPENDENT QUANTUM THEORY
Authors: XIANG TIAN-XIANG  ,   南京大学化学系,南京,210008
Published: November 2020

Collision-induced dissociation dynamic processes have been studied in this paper by using Time-dependnet quantum mechanical perturbation theory. The molecular systems are of the type of the Morse oscillator and the intermolecular exponential repulsive interaction potential. The analytical formula established can be conveniently applied to analyse a variety of physical and chemical problems relevent to CID processes. The numerical calculation for the (I2, He) system shows that vibrational energy is more effective than translational energy in enhancing the rate of the CID processes, as the total energy of the system is fixed. In addition, except the energy barrier, there are no extra dynamical restrictions for CID processes.
STIMULATED RAMAN SCATTERING OF Ti ATOMS FROM UV-LASER PHOTODISSOCIATION OF TiCl4
Authors: SHAN JUN  , LIN JIN-GU  , SHE YONG-BO  , JIN PEI  , FU KE-JIAN  , ZHANG ZHI-SAN  ,   中国科学院物理研究所,北京,100080
Published: November 2020

A large number of Ti atoms populated mainly on the ground state (a3F2) and metastable states (a3F3,4) were produced by UV-laser (259-300 nm) photodissociation of TiCl4. Many stimulated Raman scattering lines and stimulated radiations of Ti atoms were observed by pumping Ti atoms on the a3F2,3,4 states via nearly resonant transitions. All the lines observed were assigned. The pulse duration and timeresolved spectrum of SRS of Ti atoms shows the photolysis of TiCl4 to Ti atom was very fast, and the time estimated for it was less than Ins.
GROUND-STATE ENERGY OF TWO-DIMENSIONAL POLARON IN A MAGNETIC FIELD
Authors: CHEN CHUAN-YU  , JIN PEI-WAN  ,   (1)广州师范学院物理系,广州,510400; (2)中国高等科学技术中心(世界实验室)理论物理分中心
Published: November 2020

The method of the harmonic oscillator operator algebra has been used to study the two-dimensional polaron in a magnetic field. Both the surface optical phonon and the surface acoustic phonon, and their interaction with the magnetic field are included. Ground-state energy corrections up to fourth-order perturbation for limiting cases of strdng field and that in second-order perturbation for field of arbitrary strength are derived. It is found that the surface acoustic phonon makes a significant contribution to ground-state energy of a two-dimensional polaron in magnetic field.
INTERNAL FRICTION PEAK DUE TO MOVING FLUX IN Bi0.8 Pb0.2SrCaCuOy SUPERCONDUCTOR
Authors: ZHANG JIN-XIU  , ZHENG WEN-GUANG  , DU ZHONG-LIAN  , LIN GUANG-MING  , LIANG KAI-FENG  , LIN ZHI-CHENG  ,   中山大学物理系,广州,510275
Published: November 2020

The low-frequency internal friction in the magnetization process, where magnetic field increases linearly, is measured for (Bi0.8Pb0.2SrCaCuOy) in superconducting state by using a frequency variable inverted torsion pendulum system. Experimental conditions are as follows: measure temperature: 95 K, at which specimen is in resistance- free state; frequency: 0.5 Hz to 5 Hz. The characteristics of internal friction (IF) peak observed in curve of IF vs magnetic field strength H are as follows. 1. The peak height increases with an increasing of H (variance rate of magnetic field) but decreases as frequency increasing. 2. Magnetic field strength at which IF peak appears is 4-6 mT. 3. When H falis down to zero from a given value suddenly, IF peak disappears. 4. IF peak mentioned above disappears also when specimen turns to normal state.It is considered that, the eigen-IF of superconductor mentioned above during magnetization process stems from motion of quantum flux.
EFFECT OF THE PERPENDICULAR PUMPING CONFIGURATIONS ON THE SECOND-ORDER SPIN-WAVE INSTABILITY THRESHOLD IN SINGLE CRYSTAL YIG FILMS
Authors: ZHANG YOU-TING  , CHEN MING  ,   (1)Department of Physics,Colorado State University,Colorado,80523,U. S. A.; (2)上海科技大学物理系,上海,201800
Published: November 2020

This paper is to further discuss the second-order spin-wave instability processes for the ferrite sample of ellipsoidal shape using Schl?mann and Patton methods. The theoretical expressions of the second-order spin-wave instability threshold for film samples are different from Anderson-Suhl formula. The threshold calculations for single crystal YIG films under three different perpendicular pumping configurations show that the calculated thresholds are reasonably consistent with the experimental results for three configurations, and the threshold values given theoretically and experimentally are in close relationship with the oreintation of the linearly polarized microwave magnetic field.
ION BERNSTEIN WAVE COUPLING FOR POLOIDAL ELECTROSTATIC ANTENNA IN TOKAMAK
Authors: SHEN XUE-MIN  ,   中国科学院等离子体物理研究所,合肥,230031
Published: November 2020

The coupling of Ion Bernstein Wave (IBW) excited at low-field side bv poloidal electrostatic antenna to plasma using uniform plasma model has been theoretically stydied. In order to more tally with the actual situation, the finiteness of antenna poloidal length and the nonzero poloidal wave number are considered. The computation of the coupling cord shows that the poloidal electrostatic antenna is able fo excited mostly IBW in plasma. The comparison between the poloidal electrostatic antenna and the conventional toroidal antenna for instrinsic spectral impedance, input impedance and wave energy fluxes is also made, from which it is concluded that the character of coupling IBW for both antenna is quite similar.
JAHN-TELLER EFFECT AND THE STRUCTURAL PHASE TRANSITIONS IN LiNbO3 (II)
Authors: WU JIAN-BIN  , WANG ZHI-CHENG  ,   (1)上海交通大学应用物理系,上海,200030; (2)浙江大学物理系,杭州,310027
Published: November 2020

Based on the assumption of our previous paper (I), we have calculated the thermal expansion coefficients of LiNbO3 along c and b axes respectively. The results are consistent with the experiments.
MAGNETIC ANISOTROPY AND SPIN SPECTRA IN Ni-FeCr MULTILAYER FILMS
Authors: CHEN HUI-YU  , LUO YOU-QUAN  ,   中国科学技术大学物理系,合肥,230026
Published: November 2020

Ni-FeCr multilayer films were prepared by diode sputtering technique. These multilayer films exhibit magnetic uniaxial anisotropy that is shown by fitting the anglar dependence of ferromagnetic uniform resonance field. The anisotropy energy could be expressed by EK=K1sin2θ+K2sin4θ, where K2/K1≈0.59. However the behavior of surface mode suggests that che surface and interface anisotropy of these multilayer films is not of the uniaxis type. We consider that is caused by the exchange coupling at the surface and interface.
GENERATION OF TUNABLE VUV LASER NEAR 125nm BY FOUR WAVE SUM MIXING IN Hg VAPOR
Authors: ZHANG YU-KE  , ZHU BAO-QIANG  , ZOU YING-HUA  ,   北京大学物理系,北京,100871
Published: November 2020

Tunable VUV laser (ω4=2ω1+ω3) in the range of 124.80-125.06nm is gene-rated by four-wave sum mixing in Hg vapor with Ar as buffer gas, when one of the pump beams (ω1) is tuned exactly to 61S0—71S0 two-photon resonance and another pump beam (ω3) on the blue side of 71S0—91P1 transition. The experimental results are analysed with the small signal four-wave sum mixing theory. The factors affecting the best phase matching condition and the methods to expand the tunable range of VUV output in the weak pump case are discussed.
M?SSBAUER EFFECT OF VAPOR QUENCHED Fe-Pd ALLOYS
Authors: ZHANG SHENG-LIANG  , ZHAI HONG-RU  ,   南京大学物理系,南京,210008
Published: November 2020

M?ssbauer spectra were taken at 4.2 K and 290 K for the bcc and fee Fe1-xPdx alloys produced by vapor quenching. The hyperfine interaction parameters and hyperfine field distribution curves were obtained with spectrum fitting method. With increasing x, the average hyperfine field, Hhf increases in bcc Fe1-xPdx alloys, while Hhf decreases in fee alloys. The concentration dependence of Hhf can be explained by using a semi-empirical formula.
AN EXPERIMENTAL STUDY OF MORPHOLOGY DEVELOP-MENT OF SOLIDIFICATION INTERFACE
Authors: HUANG WEI-DONG  , SHANG BAO-LU  , ZHOU YAO-HE  ,   西北工业大学凝固技术国家重点实验室,西安,710072
Published: November 2020

Time-dependent development of interface morphology from initial perturbation of a planar interface to a steady periodic array of cells or dendrites was directly observed during directional solidification brocess of a transparent model alloy, succinonitrile -1.1 wt% ethanol. The following results are obtained: 1) The measured wavelength of initial perturbation of planar interface instability is within the expected wavelength range by the MS theory, but not the same as the expected wavelength with the fastest amplitude developing speed. 2) During the initial stage of a planar interface instability, the developing speed of perturbation amplitude is indeed a linear function of the amplitude, but the measured value of the amplitude developing rate is much smaller than the theoretical value. 3) The features of morphology development of cells and dendrites are different from each other, and the main cause leading to the different developing behaviour is that the relative scale of the steady primary spacing and the initial perturbation wavelength is different in the two cases.
MULTI-PHOTON SPECTRUM OF TRANSMITTED LIGHT FOR THE MIXED ABSORPTIVE-DISPERSIVE DRIVEN OPTICAL SYSTEM IN GOOD CAVITY CASE
Authors: ZHANG LIN  , LIN REN-MING  ,   福建师范大学物理系,福州,350007
Published: November 2020

In this paper, the multi-photon spectrum of transmitted light for the mixed absorptive-dispersive optical system in good cavity case is discussed. Owing to the influence of detuning θ and △, not all the various peak values of the spectrum appear at the point of ω = ω0, and the coefficient of different peak value is not the same. Therefore, the spectrum of transmitted light will show various characters, such as single peak, multi-peaks or asymmetric ones.