理论物理通讯

Select

Classical Description of Intense Field Stabilization Dynamics of 1D Model Atom

XIE Baisong, CHEN Shigang, LIU Jie

理论物理通讯. 1998, 30(4): 481-490.

摘要 ( ) PDF全文 ( )

可视化

Abstract In this paper classical nonlinear dynamics approaches are used to study the intense field stabilization (IFS) for ID model atom according to differential equation (DE) and map approximation (MA). The exact stability boundary and region of I-period fixed points in the parameter space of field strength and frequency are obtained, and the results of MA are in excellent agreement with those of DE. The electrons dynamical behavior in phase space is investigated and the IFS mainly occurring in high frequency regime is confirmed. The stabilization phenomenon connected with the stable fixed points is also examined. In particular it is shown that this phenomenon depends on tightly the KAM tori. It can be predicted that the stabilization probability is just the fraction of initial electrons confined by the KAM tori.

Select

The g Factors of Ground State of Ruby and Their Pressure-Induced Shifts

MA Dongping, ZHANG Hongmei, CHEN Jurong, LIU Yanyun

理论物理通讯. 1998, 30(4): 491-496.

摘要 ( ) PDF全文 ( )

可视化

Abstract By using the theory of pressure-induced shifts and the eigenfunctions at normal and various pressures obtained from the diagonalization of the complete d³ energy matrix adopting ,C_3v symmetry, g factors of the ground state of ruby and their pressure-induced shifts have been calculated. The results are in very good agreement with the experimental data. For the precise calculation of properties of the ground skate, it is necessary to take into account the effects of all the excited states by the diagonalization of the complete energy matrix.

Select

Scattering and Diffraction of Electromagnetic Wave by 3D Periodic Structures with Subwavelength Scales:Self-consistent Field Approach

LI Zhiyuan, GU Benyuan, YANG Guozhen

理论物理通讯. 1998, 30(4): 497-502.

摘要 ( ) PDF全文 ( )

可视化

We generalize the self-consistent field approach to deal with the problem of scattering and diffraction of electromagnetic wave by multiple obstacles. We derive in a rigorous way the relevant equations for determining the local field inside the scatterers as well as the far field of light scattering and diffraction for general periodic structures. To demonstrate the applicability of this approach, we calculate the far field distribution of the light scattering by a 30 grating. The convergent solution of the scattering field for this 30 grating can be evaluated numerically. From the comparison of the amplitudes of the diffraction factor in the 30 grating and an isolated scatterer, it is shown that the multi-scattering effect inethe 30 grating cannot be neglected. The multi-scattering effect depends on the structural parameters of the 30 grating, the incident angle, and the polarization direction of the illuminating light.

Select

First-Principles Calculations of the AS,, Electronic Structures

ZHANG Zhipeng, WU Chenxu, SHEN Yaowen, HUANG Meichun

理论物理通讯. 1998, 30(4): 503-506.

摘要 ( ) PDF全文 ( )

可视化

The changes in the GaAs electronic structure due to the arsenic-antisite defect have been calculated by using LDF-LMTO-ASA method to a D_2d-symmetry-supercell ( Ga₁₅As₁₇□₃₂)c,o ntains 15 gallium atoms, 17 arsenic atoms and 32 empty spheres. The results show that the central AsGa atom is antibonding with its nearest neighbor arsenic atoms and therefore induces gap states in GaAs. The gap states are composed of A₁-like state and T₂-like state. The bonding properties of gap states have been analyzed in detail by using density of states (DOS) and combined coefficients of wavefunctions. Our results of E_A1 =E_v+0.70 eV and= E_T2+1.07eV are in good agreement with experiments as well as previous calculation results obtained by other self-consistent methods.

Select

Conductance Fluctuation of the Normal Metal in an SNS Structure

SHI Junren, DONG Jinming, XING Dingyul, WANG Zidan

理论物理通讯. 1998, 30(4): 507-512.

摘要 ( ) PDF全文 ( )

可视化

The conductance of a clean normal metal spanning between two superconductors (SNS structure) has been investigated. It is found that the conductance fluctuates periodically with the phase difference of two superconductors. When the pairing symmetry in one side of the superconductors is d_x²-y², the fluctuation period tends to be π instead of 2π, and the phase dependence of its conductance depends strongly on the orientation of the junction in contradistinction to the s-wave case. It can be used as a new method to determine the pairing symmetry of the high-Tc superconductors.

Select

Squeezing of Phonons in Photon-Phonon Interaction via Anti-Stokes Light

CHAI Jinhua, GUO Guangcan

理论物理通讯. 1998, 30(4): 513-516.

摘要 ( ) PDF全文 ( )

可视化

A model of the photon-phonon interaction via anti-Stokes light has been proposed to investigate the squeezing properties of phonon mode. The behavior of initial anti-Stokes light with complex statistics has been studied. It is shown that the squeezing of phonon mode can appear under certain conditions.

Select

Optical Exciton Molecules in Three-Dimensional Kerr-Nonlinear Photonic Crystals

CHENG Ze

理论物理通讯. 1998, 30(4): 517-522.

摘要 ( ) PDF全文 ( )

可视化

Three-dimensional Kerr-nonlinear photonic crystals support a new kind of quantum gap solitons. Such 3D-quantum gap solitons are described by an approximate Bethe-ansatz solution of the quantized nodinear-field Hamiltonian under the effective mass approximation. Their main manifestations are predicted: (i) a series of discrete transmission peaks in the band gap, which progresses linearly with the diphoton number; (ii) Bessel-function dependence of the intensity correlation function on the detector separation.

Select

The Variational Cumulant Expansion Study of Spatially Anisotropic XY Model

LI Hong, CHEN Tianlun

理论物理通讯. 1998, 30(4): 523-526.

摘要 ( ) PDF全文 ( )

可视化

With the variational-cumulant expansion (VCE) method, the critical temperature and spontaneous magnetization of the spatially anisotropic XY model are calculated up to the fourth order. The variational parameter is determined by the complete variational method and the results are compared with both the Monte Carlo results and the self-consistent harmonic approximation (SCHA) results. It is shown that the VCE method can give a better result than the SCHA method when the coupling between adjacent layers is small.

Select

Flux in the Case of Gaussian White Noises

LI Jinghui, HUANG Zuqia

理论物理通讯. 1998, 30(4): 527-530.

摘要 ( ) PDF全文 ( )

可视化

The transport of a spatially periodic system driven by additive and multiplicative Gaussian white noises (between which there is a correlation function) is investigated. The probability current (flux) shows .that the correlation function between the additive and multiplicative noises, and the spatial asymmetry are ingredients for the flux of particles. It is a new phenomenon that the correlation function between the additive and multiplicative noises can cause transport.

Select

First-Order-Like Transition in Inhomogeneously Broadened Two-Mode Ring Laser Gain-Noise Model

LONG Quan, CAO Li, WU Dajin, LI Zaiguang

理论物理通讯. 1998, 30(4): 531-536.

摘要 ( ) PDF全文 ( )

可视化

An inhomogeneously broadened two-mode ring laser gain-noise model taking account of both full saturation effects and multiplicative noise induced by gain fluctuations is investigated. By using a corresponding Fokker-Planck equation and perturbation theory proposed by Graham et al. the joint stationary distribution for light intensities is obtained. It is found that a first-order-like transition occurs when laser is operated off resonance.

Select

Soliton Dynamics of NLS Equation at the Presence of Perturbations

YAN Jiaren, TANG Yi, ZHOU Guanghui

理论物理通讯. 1998, 30(4): 537-540.

摘要 ( ) PDF全文 ( )

可视化

A new direct approach based on the separation of variables for soliton perturbations is developed. With the aid of this approach, the effects of perturbation on a soliton of nonlinear Schrödinger (NLS) equation is obtained. In comparison with other direct methods,our approach is very concise and easy to be understood. Besides, no more approximation is employed except for the linearization of the perturbed NLS equation.

Select

Reduction Factors for O(N)⊃O(NK-1)

SUN Hongzhou, HAN Qizhi, ZHANG Mei, RUAN Dong

理论物理通讯. 1998, 30(4): 541-550.

摘要 ( ) PDF全文 ( )

可视化

In terms of the concept of irreducible tensor basis and the properties of irreducible tensor operator, we give, by mathematical induction, the irreducible representations of O(N) for (m_1Nm_2N...m_[N/2]N) and all reduction factors of O(N)⊃O(N-1) for (1 0...0)⊗(m_1Nm_2N...m_[N/2]N)

Select

Chaotic Motion of a Nucleon in Heavy Nuclei with Necked-in Shape

GU Jianzhong, WU Xizhen, ZHUO Yizhong, ZHAO Enguang

理论物理通讯. 1998, 30(4): 551-556.

摘要 ( ) PDF全文 ( )

可视化

In the framework of two-center shell model the nearest neighboring level spacing distribution and spectral rigidity of the nucleon in heavy nuclei are calculated when the shape parameters are changed systematically. Two regions of shape parameter in which the chaotic motion of the nucleon occurs are found. It is shown that the chaotic motion appears not only in the heavy nuclei with oblate shapes but also in prolate ones with a considerable neck, which is quite different from the conclusions of Ref. [2]. Bohigas Giannoni Schmit conjecture is corroborated once again by the good quantum-classical correspondence of nucleonic regular (chaotic) motion. In addition, the present work suggests that nuclear dissipation is shape-dependent,strong dissipation is expected for medium or larger separations, and provides nuclear dissipation with a dynamical understanding.

Select

Analysis of Gross Resonant Structures in ¹²C+¹²C and ¹⁶O+¹²Ne Systems Using Deep Optical Potentials

GAO Chengqun

理论物理通讯. 1998, 30(4): 557-564.

摘要 ( ) PDF全文 ( )

可视化

Abstract Within the framework of the estended optical model, the gross resonant structures of the fusion escitation functions and the elastic scattering excitation functions for the ¹²C+¹²C and the ¹⁶O+²⁰Ne systems are described well by using deep optical potentials. The origin of the gross resonant structures and the effect of the deep potential and the parity-dependent potential are discussed.

Select

Pion-Nucleus Scattering in a Hybrid Quark-Hadron Model

LIU Jifeng, YANG Chaoyun, ZHANG Yushun, B. A. Robson

理论物理通讯. 1998, 30(4): 565-570.

摘要 ( ) PDF全文 ( )

可视化

A hybrid quark-hadron model is used to describe high energy pion-alpha scattering. The parameters for the quark regime are determined by fitting pion-proton elastic scattering data. The energy dependence of both the first and the second diffraction minima in the pionalpha elastic scattering cross section is predicted. It is found that the quark degrees of freedom in pion-nucleon interaction plays a significant role, particularly, at high momentum transfer.

Select

The Dyson-Schwinger Method of the NJL Model Beyond the Mean Field Approximation

GUO Hua, LI Xiguo

理论物理通讯. 1998, 30(4): 571-576.

摘要 ( ) PDF全文 ( )

可视化

By making use of the generating functional method we derive the Dyson-Schwinger equations in the NJL model and obtain the revised quark gap equation due to the meson dressing effects (usually called beyond the mean-field correction), and finally analyze its influence on the meson properties as well as the nucleon sigma term.

Select

Electromagnetic Masses Anomaly of K^*(892) in the Massive Yang-Mills Theory

YAN Mulin, GAO Daoneng

理论物理通讯. 1998, 30(4): 577-582.

摘要 ( ) PDF全文 ( )

可视化

Electromagnetic mass difference between neutral K^* and charged K^* has been calculated in the U(3)_L×U(3)_R chiral field theory of mesons. It has been revealed that the on-Abelian gauge structure of the massive Yang-Mills Lagrangian obeyed by K^* plus VMD (vector meson dominance) causes the EM-mass of neutral one larger than charged one. Experiment supports this anomaly effect.

Select

Fermion Self-Energy and Chiral Symmetry Breaking from Four-Fermion and Gauge Interactions

ZHOU Bangrong

理论物理通讯. 1998, 30(4): 583-588.

摘要 ( ) PDF全文 ( )

可视化

The exact analytic solutions of the linearized Schwinger-Dyson equation of fermion self-energy are used to obtain the effective four-fermion and gauge coupling criticality curves for dynamical chiral symmetry breaking. The results show that when the zero-momentum gauge coupling a(0) < a₀(0), the critical gauge coupling in the pure gauge interaction case, the minimal critical four-fermion coupling β_min is always nonzero and positive and will go up as the a(0) decreases. The use of the exact solutions also allows us to make quite definite estimations of the momentum scales where chiral symmetry breaking would happen if the values of an infrared parameter ξ are given separately.

Select

Calculation of a High Order QCD Process-gg to ttgg

ZHANG Dahua, WU Dandi David Wagoner, Dennis Judd

理论物理通讯. 1998, 30(4): 589-594.

摘要 ( ) PDF全文 ( )

可视化

We use the permutation group of order 4 to classify the fouith order tree QCD Feynman diagrams, which contribute to the gg to tfgg process. (There are 159 of them.) We also provide new methods to make the color sum, and to check the gauge symmetry of the matrix elements and Feynman parts.

Select

Z₂-Symmetry Restoration in the λΦ⁴ Field Theory with Normal-Ordering Renormalization

LU Wenfa, NI Guangjiong

理论物理通讯. 1998, 30(4): 595-602.

摘要 ( ) PDF全文 ( )

可视化

Using the Gaussian wavefunctional approach plus normal-ordering renormalization, we show that for the λΦ⁴ field theory, the discrete Z₂-symmetry broken at the classical level is restored within some parameter region not only in (1+1) dimensions but also in (2+1) and (3+1) dimensions.

Select

Energy Conditions of Charged Boson Condensate and Degenerate Fermions

ZHANG Yang

理论物理通讯. 1998, 30(4): 603-608.

摘要 ( ) PDF全文 ( )

可视化

We study the energy conditions of a relativistic λΦ⁴ self-interact& charged boson condensate coupled to degenerate fermions. It is found that strong energy condition will be violated within certain range of the mass parameters and the coupling constants in the model.

Select

Dependence of the Shock Properties on the Assumption to the Flow Motion and the Shock Condition

YUAN Feng, LU Jufu

理论物理通讯. 1998, 30(4): 609-614.

摘要 ( ) PDF全文 ( )

可视化

Almost d l the authors who studied shocks in accretion flows adopted one of the two kinds of approximations to the flow: adiabatic or isothermal. And they usually adopted different shock conditions in the two cases. The calculation results of the shocks' properties, such as the.shock location and theshock strength, are greatly different in the two cases. In the present paper, we andyze the reason of the differences and show the respective effects of the assumption to the flow and of the shock condition upon the results.

Select

Power Series Expansions for Vacuum Projection Operator of Paraparticles

JING Sicong, LIAO Zhisheng, LI Hu

理论物理通讯. 1998, 30(4): 615-616.

摘要 ( ) PDF全文 ( )

可视化

Some power series expansions for the vacuum projection operator of paraboson and parafermion are derived. A recursion method is essential to these derivations of the power series expansion in terms of creation and annihilation operators of the paraparticles.

选择文件类型/文献管理软件名称

选择包含的内容

1998年, 第30卷, 第4期　
刊出日期：1998-12-15

模态框（Modal）标题

选择文件类型/文献管理软件名称

选择包含的内容

1998年, 第30卷, 第4期 刊出日期：1998-12-15

1998年, 第30卷, 第4期　
刊出日期：1998-12-15