Vol. 46, No. 1 (1997)
1997-01-05
GENERAL
1997, 46 (1): 1-11.
doi: 10.7498/aps.46.1
Abstract +
The calculation results of the stability energy of the growth unit for hydrothermal barium titanate crystallites are reported and the nucleation as well as the growth of the crystallites under hydrothermal conditions are discussed.
1997, 46 (1): 12-19.
doi: 10.7498/aps.46.12
Abstract +
We present the energy eigenvalues of modified Pschl-Teller potential,the N-dimensionalhydrogen atom,and the N-dimensional harmonic oscillator.The calculations are carried out in the framework of supersymmetry and shape invariance.The present energy spectrum formulas are consistent with the exact solutions obtained with the usual factorization method.
1997, 46 (1): 20-21.
doi: 10.7498/aps.46.20
Abstract +
Berry pointed out that the Aharonov-Bohm phase could be considered as a Berry phase.In his argument,he gave up the adiabatic approximation,and the nonstationarity of quantum states was not concerned.In this paper we re-investigate Berry’s proof,and find that his final statement is correct,and in his argument,the adiabatic approximation should be used.In the AB effect,a moving electron is described as a moving wave packet (nonstationary),and the appearance of AB phase originates from the requirement that the evolution of the wave packet must satisfy the Schrdinger equation.
1997, 46 (1): 22-27.
doi: 10.7498/aps.46.22
Abstract +
We have studied the AlOx-Al tunneling barrier in Josephson junctions by measuring XPS, AVS and Fiske step voltage.From these measurements we have found that the minimal optimum deposition Al layer thickness is 7nm in the tunneling barrier of junction that the thickness of the AlOx formed on Al only depends on oxidation condition and that the Al oxide in the tunneling barrier structure can contain an OH radical as AlOOH state.Also we evaluated the remnant Al thickness,and confirmed that the proximity effect generated by normal Al between the AlOx and low Nb exists.
1997, 46 (1): 28-34.
doi: 10.7498/aps.46.28
Abstract +
The formation of aggregation fractals in thin polycrystalline bilayer films has been simulated by using the ripening mechanism of nonuniform grains.Based on the analysis of the aggregation of thin films,three parameters are introduced:the velocity factor of grain boundary b,the relaxation range L and the curvature factor U.By using certain values of such parameters,the simulation results are consistent with the patterns formed in experiments.
NUCLEAR PHYSICS
1997, 46 (1): 35-41.
doi: 10.7498/aps.46.35
Abstract +
The α-α correlation at small relative angles has been measured for ４０Ar-induced reactions on 197Au at E/A=25MeV, in coincidence with two fission fragments. The relative populations of states of 8Be and emission temperature of hot nuclei are extracted from the α-α correlation function. The emission temperature changes slightly with the impact parameter, from about 4MeV for central collision to about 3.8MeV for peripheral collision. At peripheral collision, the emission temperature is observed to increase with the energy of particles.
ATOMIC AND MOLECULAR PHYSICS
1997, 46 (1): 42-48.
doi: 10.7498/aps.46.42
Abstract +
The purpose of this paper is to propose a theoretical treatment of radiation trapping in a multiple lines coupled system in which coupling includes collisional energy transfer and cross absorption between the excited states. First, to describe the coupled system, the Holstein equation of radiation trapping is extended to an integral differential master equation group in which the vector and matrix form is adopted. Then by use of operator manipulations, the asymptotic solution in the form of a series expansion in terms of operators is presented. Finally, the asymptotic solution is reduced, leading to a result which can not only give the system a complete description, but also has far more advantages than the simple cut off solution. A numeral illustration of a two excited states system is also presented.
1997, 46 (1): 49-55.
doi: 10.7498/aps.46.49
Abstract +
Projectile Kα satellite and hypersatellite X-ray yields were measured in collisions of Ar ions at collisional energies of 43,52,65,80,and 95MeV with targets of atomic number- Zt=6—74.The probabilities of 2s and 2p vacancy production in Ar ions were obtained,and the vacancy formation processes were analysed.
1997, 46 (1): 56-60.
doi: 10.7498/aps.46.56
Abstract +
The single electron capture cross sections for 5-30keV Ho+, La+ and Ce+ impact on H2 at a fixed anode voltage of an ion source and 10keV Ho+ impact on H2 at different anode voltage have been measured by the “growth rate method”. We found that the variation of the hollow cathode ion source’s anode voltage affected the proportion of the metastable states of the rare earth ions, and the proportion accounts for the significant change of single capture cross sections.
CLASSICAL AREA OF PHENOMENOLOGY
1997, 46 (1): 61-68.
doi: 10.7498/aps.46.61
Abstract +
In this paper, the pumping mechanism in the closed Ξ-type three-level system can be simplified using the coherence induced by the two-photon process. The system exhibits either lasing with inversion or lasing without inversion so long as there exists the pumping field. The system exhibits the transition from lasing with inverson to lasing without inversion under certain conditions. Near the transition lasing without inversion may be as efficient as lasing with inversion.
1997, 46 (1): 69-77.
doi: 10.7498/aps.46.69
Abstract +
The mode thermo stability conditions for the modes of a conventional linear resonator are developed to apply to a general resonator. The concept of weak thermo stability is introduced, and a new design method,which satisfies both the weak thermo stability conditions for the resonator modes and the thermo stability conditions for the output power, is proposed. With this method, one can make the output power thermo stable and the resonator modes partially thermo stable (for example, the divergence angle can be made thermo stable). Furthermore, analytic solutions to the strong and weak thermo stability conditions for several kinds of resonators are obtained.
1997, 46 (1): 78-86.
doi: 10.7498/aps.46.78
Abstract +
Transmitted second harmonic generation (SHG) study was made on Stilbazium salt Langmuir-Blodgett monolayer with different polarization combinations (s→p,p→p and 45°→s). The experimental data fitted in well with the transmitted SHG theoretical expressions.-And when the angle of incidence increased the theoretical data deviated from the experiments. This phenomenon may be due to the neglecting of the multiple reflection of fundamental light and harmonic light in the glass substrate on which LB monolayers were deposited. We also investigated the reasons for such deviation and gave a corrected explanation. It is found that multiple reflection in glass substrate should be considered when transmitted SHG was made with s-polarization and fixing detectors were used.
PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES
1997, 46 (1): 87-93.
doi: 10.7498/aps.46.87
Abstract +
In this paper,the nonlinear drift waves described by the Hasegawa-Mima equation have been investigated by means of analytic researches and numerical simulations.The numerical results have been shown by figures.The initial disturbances of electrostatic waves,by the nonlinear mode-coupling,will evolve into a chain of vortices,these vortices gobble up each other and some large stable vortices are formed at the final stage of the nonlinear evolution.
1997, 46 (1): 94-100.
doi: 10.7498/aps.46.94
Abstract +
By means of a high-resolution spectroscopic detection system, the radial profiles of plasma poloidal rotation velocity have been measured from the Doppler shifts of impurity ion lines OⅡ464.2nm, CⅢ464.7nm and the hydrogen Hα line on the CT-6B Tokamak. The results show that inside the plasma, the poloidal rotation velocity of impurity ions is in the electron diamagnetic drift direction and reaches its maximum value of～3.5km/s at the minor radius around 9cm. It reverses to the ion diamagnetic drift direction with its maximum value at r=10cm near the limiter. The internal electric field deduced from these data is directed towards the plasma center, and its maximum value is 18V/cm. There is also a poloidal rotation velocity component for neutral hydrogen but it is only in the electron diamagnetic drift direction with a value notably less than that of the ions. A preliminary discussion of the results is also given.
CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES
1997, 46 (1): 101-108.
doi: 10.7498/aps.46.101
Abstract +
The possible point defect configurations in alloys with L12 structure were given and the formation energies,stable configurations and volumes of point defects in Cu3Au and Au3Cu were calculated by using the molecular dynamics methods and the many-body potentials proposed by G.J.Ackland and V.Vitek.In addition,we also discussed the point defect properties of L12 structured alloy.
1997, 46 (1): 109-116.
doi: 10.7498/aps.46.109
Abstract +
By using conversion electron M?ssbauer spectroscopy (CEMS) and slow positron beam Doppler broading spectrum,the behaviour of the 57Fe implanted (100keV,3×1016 at./cm2) ZYx contained Y2O3 has been studied.The states of Fe0,Fe2+ and Fe3+ ions were obtained from CEMS for as implanted samples.After annealing at 500℃,metallic iron particles α-Fe, were formed at expense of other components. From the S-E curve of the 57Fe as implanted sample,it was found that a large amount of cationic vacancies were distributed in a region of 0—50nm in ZY3.These vacancies disappeared largely after annealing at 500℃.Therefore the parameter S provided an evidence to identify the iron sites in the implanted sample.The ZY3 appeared mingle conducting property at 300℃.It probably correlates with different iron charge states,especially with that of Fe0.
1997, 46 (1): 117-122.
doi: 10.7498/aps.46.117
Abstract +
Under the tight-binding approximation, the geometric structure of the Zn/GaAs(110) surface is calculated by a self-consistent total energy method. It is found that the surface relaxation structure is a universal characteristic for low coverage adsorption, which is important in determining the Fermi level. The bonding states are pinned at 0.73eV above the top of the valence band by the covalent hybridization of the highly localized Zn s orbitals and the surface Ga sp３ dangling bonds. A comparison is made with theoretical and experimental results of free and other adsorbate GaAs(110) surfaces.
CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
1997, 46 (1): 123-128.
doi: 10.7498/aps.46.123
Abstract +
Temperature dependence of thermoelectric power S in quasi-two dimensional potassium/sodium purple bronzes has been studied in the temperature range 80—280K.It′s found that:(1)in potassium purple bronze,S has a sign change at 105K,above which S is the small negative value and can be described by the form of S=AT+B,the dominant carriers are free electrons,in the CDW state below 105K,S is positive,and can be described by S=A′T+B′/T,the phonon-drag of the carriers is dominant; (2)in sodium purple bronze,in the studied temperature range above 80K,S has a good linear relation with temperature,no phase transition was observed,electrons may be the dominant carriers.In addition,the origins of the difference of the properties for both these isostructural crystals are also discussed briefly.
1997, 46 (1): 129-133.
doi: 10.7498/aps.46.129
Abstract +
Based on the fact that the charge is quantized in the mesoscopic circuit,the quantum theory of mesoscopic circuit has been given and the quantum fluctuation in the mesoscopic circuit has also been shown.
1997, 46 (1): 134-139.
doi: 10.7498/aps.46.134
Abstract +
The fringe effect on the third-harmonic coefficient and critical current of the fractal diffuse-fringe Au-film system, deposited on fractal substrates, is studied. We show that both the critical current and the film resistivity as exhibit functions of the third-harmonic coefficient exponential critical behavior. However, the critical exponents in the fractal diffuse-fringe Au-film are obviously different from those of other film systems. A discussion of the universality problem is also presented.
1997, 46 (1): 140-144.
doi: 10.7498/aps.46.140
Abstract +
The Lax pair formulation is presented for quantum completely integrable lattice spin open chains.Specifically,the Lax pair for the one-dimensional Heisenberg XXZ open chain with the general boundary terms is explicitly constructed.The construction provides an alternative and direct demonstration for the quantum integrability of the system.
1997, 46 (1): 145-154.
doi: 10.7498/aps.46.145
Abstract +
The nonlinear characteristics of TE surface wave on an anti-ferromagnet is studied.The nonlinear motion equation for TE wave is converted to Bernoulli differential equation and its exact solution is found in a form of inverse function.The necessary condition for the existence of nonlinear TE surface wave is μx>0.The dispersion equation and the frequency region are analyzed.The theoretical results show that the peak position of the magnetic field is not a function-of power and localized steadily at the surface of the material.In the condition of-- ε1>ε2 one guiding power corresponds two different effective refraction indexes showing the bistable property of the nonlinear TE surface waves.
1997, 46 (1): 155-161.
doi: 10.7498/aps.46.155
Abstract +
The diffusion theory shows that the displacement of space charges leads to a slow polarization effect;the response time is proportional to the square of the distance between the electrodes.The theoretical results are confirmed in experiments.A method of differential time domain spectroscopy is used to study the existence and movement of space charges in C6H6 and CH3 (CH2)n CH3.There are one fast component and two slow components in these compounds.Their response times and strength give information about the molecular length and motion at various temperatures.This differential dielectric spectroscopy in the time domain is a very sensitive method for trace analysis of inpurities in highly insulating liquids.
