2018年, 第69卷, 第06期　
刊出日期：2018-06-01

  

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  Residual Symmetry Reduction and Consistent Riccati Expansion of the Generalized Kaup-Kupershmidt Equation

  刘希忠, 俞军, 楼智美, 曹巧君

  理论物理通讯. 2018, 69(06): 625-630.

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  The residual symmetry of the generalized Kaup-Kupershmidt (gKK) equation is obtained from the truncated Painlevé expansion and localized to a Lie point symmetry in a prolonged system. New symmetry reduction solutions of the prolonged system are given by using the standard Lie symmetry method.Furthermore,the gKK equation is proved to integrable in the sense of owning consistent Riccati expansion and some new Bäcklund transformations are given based on this property, from which interaction solutions between soliton and periodic waves are given.
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  Bifurcations and Dynamics of Traveling Wave Solutions to a Fujimoto-Watanabe Equation

  师利娟, 温振庶

  理论物理通讯. 2018, 69(06): 631-636.

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  In this paper, we study the bifurcations and dynamics of traveling wave solutions to a Fujimoto-Watanabe equation by using the method of dynamical systems. We obtain all possible bifurcations of phase portraits of the system in different regions of the parametric space. Then we show the sufficient conditions to guarantee the existence of traveling wave solutions including solitary wave solutions, periodic wave solutions, compactions and kink-like and antikink-like wave solutions. Moreover, the expressions of solitary wave solutions and periodic wave solutions are implicitly given, while the expressions of kink-like and antikink-like wave solutions are explicitly shown. The dynamics of these new traveling wave solutions will greatly enrich the previews results and further help us understand the physical structures and analyze the propagation of the nonlinear wave.
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  A Novel Method to Solve Nonlinear Klein-Gordon Equation Arising in Quantum Field Theory Based on Bessel Functions and Jacobian Free Newton-Krylov Sub-Space Methods

  K. Parand, M. Nikarya

  理论物理通讯. 2018, 69(06): 637-644.

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  The Klein-Gordon equation arises in many scientific areas of quantum mechanics and quantum field theory. In this paper a novel method based on spectral method and Jacobian free Newton method composed by generalized minimum residual (JFNGMRes) method with adaptive preconditioner will be introduced to solve nonlinear Klein-Gordon equation. In this work the nonlinear Klein-Gordon equation has been converted to a nonlinear system of algebraic equations using collocation method based on Bessel functions without any linearization, discretization and getting help of any other methods. Finally, by using JFNGMRes, solution of the nonlinear algebraic system will be achieved. To illustrate the reliability and efficiency of the proposed method, we solve some examples of the Klein-Gordon equation and compare our results with other methods.
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  A New Treatment for Some Periodic Schrödinger Operators Ⅱ: The Wave Function

  贺伟

  理论物理通讯. 2018, 69(06): 645-654.

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  Following the approach of our previous paper we continue to study the asymptotic solution of periodic Schrödinger operators. Using the eigenvalues obtained earlier the corresponding asymptotic wave functions are derived. This gives further evidence in favor of the monodromy relations for the Floquet exponent proposed in the previous paper. In particular, the large energy asymptotic wave functions are related to the instanton partition function of N=2 supersymmetric gauge theory with surface operator. A relevant number theoretic dessert is appended.
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  Electroosmotic Flow of MHD Power Law Al₂O₃-PVC Nanofluid in a Horizontal Channel: Couette-Poiseuille Flow Model

  N. Shehzad, A. Zeeshan, R. Ellahi

  理论物理通讯. 2018, 69(06): 655-666.

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  The current manuscript is reported about the electro-osmotic Couette-Poiseuille flow of power law Al₂O₃-PVC nanofluid through a channel, in which upper wall is moving with constant velocity. The influences of magnetic field, mixed convection, joule heating, and viscous dissipation are also incorporated. The flow is generated because of constant pressure gradient in axial direction. The resulting flow problem is coupled nonlinear ordinary differential equations, which are at first modeled and then transform into dimensionless form through appropriate transformation. Analytical solution of the governing is carried out. The impact of modified Brinkman number, modified Magnetic field, electro-osmotic parameters on velocity and temperature are examined graphically. From the results, it is concluded that the Skin friction at moving isolated wall decreases with the increase of electro-osmotic parameter and reverse behavior for Nusselt number at heated stationary wall occur.
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  Natural Convection of Fe₃O₄-Ethylene Glycol Nanofluid under the Impact of Electric Field in a Porous Enclosure

  M. Sheikholeslami, S. A. Shehzad, R. Kumar

  理论物理通讯. 2018, 69(06): 667-675.

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  Free convection of Fe₃O₄-Ethylene glycol nanofluid in existence of Coulomb forces is studied. Effect of thermal radiation is taken into account. Properties of nanofluid are varied with supplied voltage and shape of nanoparticles. The bottom wall is considered as positive electrode. Control Volume based Finite Element Method is used to obtain the results, which are the roles of Darcy number (Da), radiation parameter (Rd), Rayleigh number (Ra), nanofluid volume fraction (?), and supplied voltage (△φ). Results indicate that Nusselt number is an enhancing function of supplied voltage and Darcy number. Maximum values for temperature gradient are occurred for platelet shape nanoparticles.
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  Stability Analysis of Solitary Wave Solutions for Coupled and (2+1)-Dimensional Cubic Klein-Gordon Equations and Their Applications

  Aly R. Seadawy, Dian-Chen Lu, Muhammad Arshad

  理论物理通讯. 2018, 69(06): 676-686.

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  The searching exact solutions in the solitary wave form of non-linear partial differential equations (PDEs) play a significant role to understand the internal mechanism of complex physical phenomena. In this paper, we employ the proposed modified extended mapping method for constructing the exact solitary wave and soliton solutions of coupled Klein-Gordon equations and the (2+1)-dimensional cubic Klein-Gordon (K-G) equation. The Klein-Gordon equations are relativistic version of Schrödinger equations, which describe the relation of relativistic energy-momentum in the form of quantized version. We productively achieve exact solutions involving parameters such as dark and bright solitary waves, Kink solitary wave, anti-Kink solitary wave, periodic solitary waves, and hyperbolic functions in which several solutions are novel. We plot the three-dimensional surface of some obtained solutions in this study. It is recognized that the modified mapping technique presents a more prestigious mathematical tool for acquiring analytical solutions of PDEs arise in mathematical physics.
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  Implementation Scheme of Two-Photon Post-Quantum Correlations

  潘国柱, 储文静, 杨名, 杨青, 张刚, 曹卓良

  理论物理通讯. 2018, 69(06): 687-693.

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  The pre-and post-selection processes of the "two-state vector formalism" lead to a fair sampling loophole in Bell test, so it can be used to simulate post-quantum correlations. In this paper, we propose a physical implementation of such a correlation with the help of quantum non-demolition measurement, which is realized via the cross-Kerr nonlinear interaction between the signal photon and a probe coherent beam. The indirect measurement on the polarization state of photon is realized by the direct measurement on the phase shift of the probe coherent beam, which enhances the detection efficiency greatly and leaves the signal photon unabsorbed. The maximal violation of the CHSH inequality 4 can be achieved by pre-and post-selecting maximally entangled states. The reason why we can get the post-quantum correlation is that the selection of the results after measurement opens fair-sampling loophole. The fair-sampling loophole opened here is different from the one usually used in the currently existing simulation schemes for post-quantum correlations, which are simulated by selecting the states to be measured or enlarging the Hilbert space. So, our results present an alternative way to mimic post-quantum correlations.
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  Destroying a Near-Extremal Kerr-Newman-AdS Black Hole with Test Particles

  宋宇, 张明, 邹德成, 孙成一, 岳瑞宏

  理论物理通讯. 2018, 69(06): 694-698.

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  If radiative and self-force effects are neglected, we find that feeding a test particle into a near-extremal Kerr-Newman-AdS black hole could lead to destroy their event horizon, giving rise to naked singularities. Hence radiative and self-force effects must be taken into account to further test cosmic censorship. Moreover, the allowed parameter range for this test particle is very narrow, this leaves the possibility of radiative and self-force effects considerations to cure the problem of WCC violation in Kerr-Newman-AdS spacetime.
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  Ordinary Mode Instability in a Cairns Distributed Electron Plasma

  K. Azra, Z. Iqbal, G. Murtaza

  理论物理通讯. 2018, 69(06): 699-703.

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  Employing the linearized Vlasov-Maxwell equations, a generalized dispersion relation for the ordinary mode is derived by employing the Cairns distribution function. The instability of the mode and its threshold condition is investigated. It is found that the temperature anisotropy χ=T_||/T_⊥>1 required to excite the instability varies with density values whereas the growth rate is dependent on various parameters like non-thermality Λ, equilibrium number density n₀ and temperature anisotropy. It is found that with the increase in the values of any of the parameters Λ, n₀ and χ, the growth rate is enhanced and the k-domain is enlarged. The results are applicable for space plasma environments like solar wind.
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  Thermal Conductivity of Complex Plasmas Using Novel Evan-Gillan Approach

  Aamir Shahzad, Syed Irfan Haider, Muhammad Kashif, Muhammad Shahzad Shifa, Tariq Munir, Mao-Gang He

  理论物理通讯. 2018, 69(06): 704-710.

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  The thermal conductivity of complex fluid materials (dusty plasmas) has been explored through novel Evan-Gillan homogeneous non-equilibrium molecular dynamic (HNEMD) algorithm. The thermal conductivity coefficient obtained from HNEMD is dependent on various plasma parameters (Γ, κ). The proposed algorithm gives accurate results with fast convergence and small size effect over a wide range of plasma parameters. The cross microscopic heat energy current is discussed in association with variation of temperature (1/Γ) and external perturbations (P_z). The thermal conductivity obtained from HNEMD simulations is found to be very good agreement and more reliable than previously known numerical techniques of equilibrium molecular dynamic, nonequilibrium molecular dynamic simulations. Our new investigations point to an effective conclusion that the thermal conductivity of complex dusty plasmas is dependent on an extensive range of plasma coupling (Γ) and screening parameter (κ) and it varies by the alteration in these parameters. It is also shown that a different approach is used for computations of thermal conductivity in 2D complex plasmas and can be appropriate method for behaviors of complex systems.
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  Spontaneous Emission Originating from Atomic BEC Interacting with a Single-Mode Quantized Field

  E. Ghasemian, M. K. Tavassoly

  理论物理通讯. 2018, 69(06): 711-721.

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  In this paper we present a general theoretical model for the interaction between a number of two-level atoms constituting Bose-Einstein condensate (BEC) and a single-mode quantized field. In addition to the usual interacting terms, we take into account interatom as well as higher-order atom-field interactions. To simplify the Hamiltonian of system, after using the Bogoliubov approximation we proceed to calculate the transformed operators of atoms and field. Then, to quantify the spontaneous emission, we get analytical expressions for the expectation value of ?_z as the atomic population inversion (API), in the cases of number and coherent states for the atomic subsystem. Our results show that the above-mentioned model interaction leads to the appearance of collapse-revival phenomenon in API. In more detail, the revival time may be tuned by adjusting the interatom interaction constant. Also, the damping process lowers the amplitude of API, but does not change the CR times for weak damping. Moreover, increasing the damping may decrease the number of CRs in a given interval of time such that no revival occurs. Briefly, it may be concluded that in the resonant case the revival times are insensitive to the change of the higher-order atom-field interaction constant and are affected only by the interatom interactions. Finally, we express that, how we can find a practical procedure to measure the quantum states of atoms in BEC.
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  Thermodynamic Nonequilibrium Features in Binary Diffusion

  林传栋, 罗开红, 甘延标, 赖惠林

  理论物理通讯. 2018, 69(06): 722-726.

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  Diffusion is a ubiquitous physical phenomenon where thermodynamic nonequilibrium effects (TNEs) are outstanding issues. In this work, we employ the discrete Boltzmann method to investigate the TNEs in the dynamic process of binary diffusion. The main features of the distribution function in velocity space are recovered and discussed. It is found that, with the decreasing gradients of macroscopic quantities (such as density, concentration, velocity, etc.), both the local and global TNEs decrease with the time but increase with the relaxation time in a power law, respectively.
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  Statistical Properties of a System Consisting of a Superconducting Qubit Coupled to an Optical Field Inside a Transmission Line

  Clodoaldo Valverde, Gabriela Rodrigues Vaz, Vitor Teles de Oliveira, Basílio Baseia

  理论物理通讯. 2018, 69(06): 727-734.

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  The present work investigates the entropy and the excitation inversion of a coupled system that consists of a qubit represented by a Cooper pair box (CPB) interacting with a transmission line working as a circuit quantum electrodynamics (CQED). The proposed scheme uses the Buck-Sukumar model with a time dependent frequency in the presence of losses to study the evolution of the entropy and the excitation inversion of the system. We have shown that the CQED is much more sensitive to the presence of losses than the CPB. The results also show that it is possible to monitor properties of the subsystems through appropriate choices of the time-dependent parameters.
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  Molecular Dynamics Simulations of the Elastic Anisotropy of Pd at Extreme Conditions

  张修路, 韩运侠, 贾红, 曲诺, 刘中利

  理论物理通讯. 2018, 69(06): 735-740.

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  It is very interesting to discover the elastic properties of engineering material palladium, especially its elastic anisotropy along Hugoniot states. We here investigate the evolution of its high pressure and temperature (PT) elastic ansotropy along Hugoniot using molecular dynamics simulations based on accurate classical interatomic potential. In order to testify the validity of the interatomic potential of Pd in describing the high PT elastic properties, we calculate its isothermal and adiabatic elastic moduli using molecular dynamics method. The obtained data are in good agreement with experimental data. From the isothermal elastic constants, we deduce the Hugoniot acoustic velocities and find that the resulting data are in good agreement with experimental acoustic velocity data. Based on the reliable elastic constants, we further investigate the spacial elastic ansotropy along Hugoniot PT states. It is found that the spacial elastic anisotropy of Pd increases along Hugoniot states.
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  Influences of Crystal-Field and Interlayer Coupling Interactions on Dynamic Phase Diagrams of a Mixed-Spin (3/2, 2) Bilayer System

  Mustafa Keskin, Yusuf Koçak

  理论物理通讯. 2018, 69(06): 741-748.

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  Influences of crystal-fields (D_A and D_B) and interlayer coupling interactions (J₃) on dynamic magnetic critical behaviors of a mixed-spin (3/2, 2) bilayer system under an oscillating magnetic field are investigated by the Glauber-type stochastic dynamics based on the mean-field theory. For this purpose, dynamic phase diagrams are constructed in the reduced temperature and magnetic field amplitude plane for the ferromagnetic/ferromagnetic (FM/FM), antiferromagnetic/ferromagnetic (AFM/FM) and AFM/AFM interactions in detail. We observe that the influences of D_A, D_B and J₃ interactions parameters on the behavior of the dynamic phase diagrams are very much.