Vol. 42, No. 3 (1993)
1993-02-05
GENERAL
1993, 42 (3): 345-350.
doi: 10.7498/aps.42.345
Abstract +
In the reference [1] , we have given the exact solutions of both bound and scattering sfa-tes for one dimensional Schr?dmger equation with potential V(x)=-N(N +1l)sech2x in the case of arbitrary positive integer N. In the present work we extend the results of [1] to three dimensional case, and find some physical significance which is different from that in one di-mensional case.
1993, 42 (3): 351-359.
doi: 10.7498/aps.42.351
Abstract +
In this paper the transformation between the volumetric and sectional size distribution of the disordered meso-structures is studied. An integral equation governing this transformation for the cases of spheres or parallel penny shaped cracks is derived. The statistical interpretation on the transformation equation is emphasized. Furthermore, the transformations for moments of distribution function and for fractal dimension are discussed.
THE PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
1993, 42 (3): 360-367.
doi: 10.7498/aps.42.360
Abstract +
This paper presents the results of inves'igation on the influence of HF, HC1, H2SO4 and HAC on the liquid crystal structure of phosph tidyle-thandamine(PE) by means of the me-thod of small angle x-ray scattering method. The experiment shows that: HF exhibits the me-chanism that makes PE liquid crystal sta'e to transform into C phase; HC1 exhibits the me-chanism of transforming into LH phase; H results in La phase; and HAC results in LH phase via La phase.
NUCLEAR PHYSICS
1993, 42 (3): 368-372.
doi: 10.7498/aps.42.368
Abstract +
The cranked shell model (CSM) and particle rotor model (PRM) are exactly diagona-lized in j = ll/2 shell with particle number conserving method and the variations of pair cor-relation with angular momentum are systematically investigated. From the comparsion of pair gap parameter, spectra, spin alignment and seniority structure of yrast band for CSM and PRM, the validity of CSM is discussed.
ATOMIC AND MOLECULAR PHYSICS
1993, 42 (3): 373-378.
doi: 10.7498/aps.42.373
Abstract +
In the paper, we genesalize the dressed state theory including the second-order ionization and the autoionizing coupling to study the effects of second-order ionization on the stability of the dressed state. It is showed that the second-order ionization destroys the stability and the C-C coupling, however, reduces the instability to some degrees.
1993, 42 (3): 379-384.
doi: 10.7498/aps.42.379
Abstract +
Based on Dirac-Fock, Dirac-Slater, Hartree-Fock and Hartree-Slater self-consistent-field methods, we have conducted calculations of reduced normalization factors of occupied shell wavefunctions of nitrogon, iron, and uranium atoms as well as nitrogon-like inon and uranium ions. Their dependence on various coupling terms as well as relativistic effects and effects of the Slater local electron density approximation are discussed.
1993, 42 (3): 385-393.
doi: 10.7498/aps.42.385
Abstract +
A quantum well dot model of ultra-fine particles (UFP) is presented in this paper. It is assumed that principal UFP characteristics are determined by non-localized electrons, which are restricted within a three-demensional potential well with finite depth (quantum well dot). Electronic characteristics are contributed by both of single-electron behavior and collective be-haviors. The electron energy spectrum is mainly determined by single-electron behavior. The model reflects the atomic properties, such as bulk work funtion, atomic radius and first ioni-zing energy value, and ignores the finer UFP structures. The approximation is proved rea-sonable. A number of useful formulae and predictions are derived. (1) The famous UFP cha-racteristics, quantum size effect and shell structures of electron energy spectrum, are derived from the quantum well dot model. (2) The UFP work function and Fermi-energy level, which is diffi-cult to be obtained by other models, are calculated. The formula that expresses the work func tion xarying with UFP size variation is derived, which explains well the experiments. The work function increases at first and then decreases gradually to bulk one with UFP size in-creasing. (3) The average energy space (AES) near Fermi- energy and the relationship bet-ween AES and electron interaction are derived. And the famous Kubo formula can be derived from quantum well dot model. (4) Finally, the model predicts the existence of electron energy subbands in UFP and semiconductor behavior of metallic UFP in some size. When particle size increases the sub-bands can not be discriminated and finally disappears, the particle shows complete bulk characteristics.
CLASSICAL AREA OF PHENOMENOLOGY
1993, 42 (3): 394-399.
doi: 10.7498/aps.42.394
Abstract +
In the present paper, starting from the Fresnel diffraction theory, we analyzed die dif-fraction image properties of the optical element arrays(OEA) and obtained the point spread function. We also examined the composite imaging properties of the OEA, obtained the con-ditions under which an OEA can form composite images.
1993, 42 (3): 400-406.
doi: 10.7498/aps.42.400
Abstract +
In this paper, a method for constructing every orthonormal eigenstates system of αN is given with N basic vecrors of coherent states |a exp(i2πn/N) > (n = 0,1, … N-1). Squeezing and antibunching in these states are studied. The results show that αN have the orthonormal eigenstates system which exhibits amplitude m-th (m
1993, 42 (3): 407-416.
doi: 10.7498/aps.42.407
Abstract +
In this paper a "convection-nonequilibrium cross relaxation" theory is presented for a gas flow and chemical lasers: The experessions of gain coefficienr and saturated gain spec-trum are derived for the two-type flow models of a gas flow medium with turbulent or lami-nar flow mixture respectively. Some new gain saruration laws are obtained. The unsaturated and saturated gain are dependent on the streamwise distance. The numerical results show that the gain profiles of a saturated amplifier with Doppler-broadening presents some "anoma-lous" phenomena with a mixture of inhomogeneous and homogeneous profiles. The present theoretical results agree with the measured results
1993, 42 (3): 417-421.
doi: 10.7498/aps.42.417
Abstract +
This paper reports the theoretical calculation of the ambipolar diffusion coefficient in TDFWM-IL. We have obtained the ambipolar diffuion coefficient Da= 0.3cm2/s for CdS:Cu and compared with measured results for PbS ultrafine particles.
1993, 42 (3): 422-430.
doi: 10.7498/aps.42.422
Abstract +
The third harmonic generation spectrum (THG) of trans-polyacetylene exhibits two peaks at 0.6eV and 0.9 eV respectively. None of the existing theories can give a quantitatively satis-factory interpretation. By considering properly the excitation-dependent damping, we can get the second peak at 0.9eV. The damping of excited states that we depict in this paper due to electron-phonon interaction of polymer varies with the excited states. According to this dam-ping, the theoretical results of THG agree with the observed spectrum very well.
PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES
1993, 42 (3): 431-436.
doi: 10.7498/aps.42.431
Abstract +
The interactions of two-frequency laser with Langmuir wave in a plasma beat-wave acce-lerator are calculated. We show that the development of the Langmuir wave from initial stage to saturation is closely correlated to the evolution of the three waves involved from phase locking to phase mismatching. The phase difference, describing the extent of three-wave coup-ling, is therefore of great importance in Langmuir-wave excitation by beating two-frequency la-ser.
CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES
1993, 42 (3): 437-445.
doi: 10.7498/aps.42.437
Abstract +
The formula of harmonic diffraction from a perfect crystal is worked out based on the concept of dynamical diffraction and the spectrum of synchrotron radiation. As an applica-tion, the harmonic diffraction from several commonly used planes of Si crystal is calculated, which reveals that there are more harmonics in the chosen (333) diffraction than the other planes. The data are merely true for the Topography Station at Beijing Synchrotron Radia-tion Lab. (BSRL), Beijing Electron-Positron Collider (BEPC).
1993, 42 (3): 446-452.
doi: 10.7498/aps.42.446
Abstract +
Error analysis is carried out systematically for Voigt function method. The rules of error are obtained, and described in the form of formula and diagrams. The reliability regime of this method is also given.
1993, 42 (3): 453-457.
doi: 10.7498/aps.42.453
Abstract +
The bonding structure of laser-prepared nanometer a-SixNy:H powder and the bulk body prepared by pressing of powder are studied by IR and Raman spectroscopy. It is found that there are Si-N Si-Si, Si-H, N-H, Si-O-Si bonds and OH group in a-SixNy:H. The distortion of the spectra and the change of bonding structure of the bulk body before and after annealing are discussed.
1993, 42 (3): 458-464.
doi: 10.7498/aps.42.458
Abstract +
Low tempterature internal friction peaks in cold-worked Al-Mg solid solutions were sys-tematically studied. Two internal friction peaks were observed around - 70℃ (PL2 peak) and - 50℃ (PL1 peak) when measured with a frequency of about IHz. Effect of magnesium con-tent, amount and mode of cold-working, type of solute atoms, and annealing on the appearan-ce and behavior of these two peaks were examined. Conclusions were reached thai PL2 peaks is associated with the interaction of dislocations with ‘Mg atom-divacancy' pairs and PL1 peak is associated with the interaction of dislocations with ‘Mg atom-vacancy' pairs.
1993, 42 (3): 465-469.
doi: 10.7498/aps.42.465
Abstract +
Small amount of rare-earth elements may have negative effects on the formation of some metallic glass alloys. The rare-earth elements may react with some atoms of the alloys to form compounds of high melting points or be absorbed on the surfaces of the heterogeneous catalysts in the alloys to activate the heterogeneous nucleation. In this case, the rare-earth elements have no effects on enhancing the stability of the metallic glass phase but enhance the heterogeneous nucleation and decrease the metallic glass forming ability and thermostability.
1993, 42 (3): 470-476.
doi: 10.7498/aps.42.470
Abstract +
Using a cluster model Pt21O2, the interaction of O2 with Pt(lll) surface has been studied by means of the atom superposition and electron delocalization-molecular orbital (ASED-MO) theory. From the total energy minimization, we found that the O2 lying-down orientations are favored over the upright orientations, and the chemisorption on bridge site with O-O axis along the bridge is the most stable. The resulting O2 bond length is 1.35?, which is consistent with the latest NEXAFS result of (1.37 ±.05)?. The charge transferred from the substrate to the O2 molecule is about 0.6e, which is mainly filled in the O2 antibonding lπg orbital. An ac-tivation barrier of 0.20eV is found in the dissociation of the π-bonded O2 on the bridge sites. The dissociated O adatoms favor the 3-fold (hcp) hollow sites with a Pt-O bond length of 1.95?. Furthermore, a detailed calculation for local density of states (LDOS) are performed to find the components and origins of UPS features. Finally, a general discussion is given for the O2 phy-sisorption on Pt(lll).
CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
1993, 42 (3): 477-481.
doi: 10.7498/aps.42.477
Abstract +
The energy bands of CdTe are studied using the method of Orthogonalized Linear Com-bination of Atomic Orbitals (OLCAO). The risults are in good agreement with that given by methods of LAPW, LMTO-ASA and NL-EPM. Some physical quantities related to the optical properties of CdTe are also described. These are the imaginary component of optical dielec-tric function ∈2(ω), and that of high frequency conductivity σ1(ω), and the optical reflectivity R(∈)
1993, 42 (3): 482-487.
doi: 10.7498/aps.42.482
Abstract +
Ar ion implantation induced superconductivity change and structural change in YBa2Cu3O7-x epitaxial films have been studied. After implantation, not only Jc and Tc of the sa-mples decreased with the increasing of Ar ion fluence, but also a metal-to-semiconducfor transition occurred. The TEM photographs showed that the lattice frame of the implanted sa-mples was nearly unchanged under low fluence. Only at high fluence, the structure was comple-tely destroyed. According to the experimental results, we suggest that the degradation of Jc and Tc may mainly result from the disordering of oxygen sublattice.
1993, 42 (3): 488-495.
doi: 10.7498/aps.42.488
Abstract +
By employing the imaginary time functional technique and the so-called replica method, a quantum vector spin glass model with random Dzyaloshinskii-Moriya anisotropy and ferro-magnetic interaction is investigated for any spin quantum numbers. In the static replica sym-metry limit, the spin self-interaction order parameters, the spin glass order parameters and the magnetization are all determined self-consistently. The relation between susceptibility tensors and order parameters is set up. Compared with other methods, our theory works at all tempe-ratures.
1993, 42 (3): 496-505.
doi: 10.7498/aps.42.496
Abstract +
A theoretical study of the properties of the ground state and excited state of FH(CN)- de-fect pair in KC1 crystal has been conducted by using the SLC extended-ion method. The resul-ts of the calculation for electronic absorption and emission are in good agreement with the ex-periments. Under the harmonic approximation, we calculate the frequencies of the (CN)- stretching vibration. It is reasonable to attribute the observed splitting into four components in Ra-man vibrational spectrum to the four inequivalent (CN)- orientations with respect to the [110] neighboring F centre. Finally, the e-v energy transfer processes has been studied, It is pointed out that during the relaxation process polarization causeed by the change in F electrcr nic state would excite the (CN)- stretching mode from m = 0 to m = l.
GEOPHYSICS, ASTRONOMY, AND ASTROPHYSICS
1993, 42 (3): 506-512.
doi: 10.7498/aps.42.506
Abstract +
The radiative temperature of a non-uniformly rectilinearly accelerating evaporating bla-ck hole is presented. The temperature is dependent on the time, and it is not constant on the simultaneity section of the event horizon. The location of simultaneity section of the event ho-rizon depends on the time, and its shape is not spherically symmetric.
