Communications in Theoretical Physics

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Holomorphic Factorization of Superstring Scattering Amplitudes

Simon Davis

Abstract （708）

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The holomorphic factorization of the superstring partition function is verified at arbitrary genus. The evaluation of scattering amplitudes and the implications of genus-dependent estimates on the string coupling are given.

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Double Integrable Couplings and Their Constructing Method

GUO Fu-Kui and ZHANG Yu-Feng

Communications in Theoretical Physics

Abstract （718）

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To extend the study scopes of integrable couplings, the notion of double integrable couplings is proposed in the paper. The zero curvature equation appearing in the constructing method built in the paper consists of the elements of a new loop algebra which is obtained by using perturbation method. Therefore, the approach given in the paper has extensive applicable
values, that is, it applies to investigate a lot of double integrable couplings of the known integrable hierarchies of evolution equations. As for explicit applications of the method proposed in the paper, the double integrable couplings of the AKNS hierarchy and the KN hierarchy are worked out, respectively.

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Lump Solutions of Kadomtsev-Petviashvili I Equation in Non-uniform Media

ZHU Xiao-Ming, ZHANG Da-Jun, and CHEN Deng-Yuan

Communications in Theoretical Physics

Abstract （700）

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N-lump solutions of the Kadomtsev-Petviashvili I equation in non-uniform media are derived through the inverse scattering transform. The obtained solutions describe lump waves with time-dependent amplitudes and velocities. Dynamics of 1-lump wave and interactions of two lump wave are illustrated.

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Wronskian and Grammian Solutions for (2+1)-Dimensional Soliton Equation

ZHANG Yi, CHENG Teng-Fei, DING Da-Jun, and DANG Xiao-Lan

Communications in Theoretical Physics

Abstract （672）

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In this paper, the (2+1)-dimensional soliton equation is mainly being discussed. Based on the Hirota direct method, Wronskian technique and the Pfaffian properties, the N-soliton solution, Wronskian and Grammian solutions have been generated.

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Pseudopotentials, Lax Pairs and Bäcklund Transformations for Generalized Fifth-Order KdV Equation

YANg Yun-Qing and CHEN Yong,

Communications in Theoretical Physics

Abstract （645）

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Based on the method developed by Nucci, the pseudopotentials, Lax pairs and the singularity manifold equations of the generalized fifth-order KdV
equation are derived. By choosing different coefficient, the corresponding results and the Bäcklund transformations can be obtained on three conditioners which include Caudrey-Dodd-Gibbon-Sawada-Kotera equation, the Lax equation and the Kaup-kupershmidt equation.

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Modelling and Simulation for Train Movement Control Using Car-FollowingStrategy

LI Ke-Ping, GAO Zi-You, and TANG Tao

Communications in Theoretical Physics

Abstract （726）

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Based on optimal velocity car-following model, in this paper, we propose a new railway traffic model for describing the process of train movement control. In the proposed model, we give an improved form of the optimal velocity function V^opt, which is considered as the desired velocity function for train
movement control under different control conditions. In order to test the proposed model, we simulate and analyze the trajectories of train movements, moreover, discuss the relationship curves between the train allowable velocity and the site of objective point in detail. Analysis results indicate that the proposed model can well capture some realistic futures of train movement control.

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Solution of Dirac Equation with Killingbeck Potential by Using WaveFunction Ansatz Method under Spin Symmetry Limit

M. Hamzavi and A.A. Rajabi

Communications in Theoretical Physics

Abstract （558）

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The Dirac equation is solved for Killingbeck potential. Under spin symmetry limit, the energy eigenvalues and the corresponding wave functions are obtained by using wave function ansatz method.

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Solution of Dirac Equation with Killingbeck Potential by Using Wave Function Ansatz Method under Spin Symmetry Limit

M. Hamzavi and A.A. Rajabi

Communications in Theoretical Physics

Abstract （678）

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The Dirac equation is solved for Killingbeck potential. Under spin symmetry limit, the energy eigenvalues and the corresponding wave functions are obtained by using wave function ansatz method.

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New Formulation of Weyl Quantization Scheme in Coherent State Representation

LIU Tang-Kun and FAN Hong-Yi

Communications in Theoretical Physics

Abstract （688）

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By virtue of the technique of integration within an ordered product of operators we present a new formulation of the Weyl quantization scheme in the coherent state representation, which not only brings convenience for calculating the Weyl correspondence of normally ordered operators, but also directly leads us to find both the coherent state representation and the Weyl ordering representation of the Wigner operator.

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Dynamics of Quantum Discord in Asymmetric and Local Non-Markovian Environments

HAO Xiang, PAN Tao, SHA Jin-Qiao, and ZHU Shi-Qun

Communications in Theoretical Physics

Abstract （632）

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The non-Markovian decoherence of quantum and classical correlations
is analytically obtained when two qubits are asymmetrically subjected to the bit flip channel and phase flip channel. For one class of initial mixed states, quantum correlations quantified by quantum discord decay synchronously with classical correlations. The discovery that the decaying rates of quantum and classical correlations suddenly change at the characteristic time is
physically interpreted by the distance from quantum state to the closest classical states. In a large time interval, quantum correlations are greater than classical correlations. The quantum and classical correlations can be preserved over a longer period of time via the kernel characterizing the environment memory effects.

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Enhanced KR-Fundamental Measure Functional for Inhomogeneous Binary and Ternary Hard Sphere Mixtures

ZHOU Shi-Qi

Communications in Theoretical Physics

Abstract （674）

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An enhanced KR-fundamental measure functional (FMF) is elaborated and
employed to investigate binary and ternary hard sphere fluids near a planar
hard wall or confined within two planar hard walls separated by certain
interval. The present enhanced KR-FMF incorporates respectively, for aim of
comparison, a recent 3rd-order expansion equation of state (EOS) and a
Boublik's extension of Kolafa's EOS for HS mixtures. It is indicated that the two versions of the EOS lead to, in the framework of the enhanced KR-FMF, similar density profiles, but the 3rd-order EOS is more consistent with an exact scaled particle theory (SPT) relation than the BK EOS. Extensive comparison between the enhanced KR-FMF-3rd-order EOS predictions
and corresponding density profiles produced in different periods indicates
the excellent performance of the present enhanced KR-FMF-3rd-order EOS in
comparison with other available density functional approximations (DFAs).
There are two anomalous situations from whose density profiles all DFAs
studied deviate significantly; however, subsequent new computer simulation
results for state conditions similar to the two anomalous situations are in
very excellent agreement with the present enhanced KR-FMF-3rd-order EOS. The present paper indicates that (i) the validity of the ``naive'' substitution
elaborated in the present paper and peculiar to the original KR-FMF is still
in operation even if inhomogeneous mixtures are being dealt with; (ii) the
high accuracy and self-consistency of the third order EOS seem to allow for
application of the KR-FMF-third order EOS to more severe state conditions;
and (iii) the ``naive'' substitution enables very easy the combination of the
original KR-FMF with future's more accurate but potentially more complicated
EOS of hard sphere mixtures.

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Cavity-Induced Self-Trapping of a Bose Josephson Junction

HUANG Jin-Song, XIE Zheng-Wei, YAN Cong-Hua,, and WEI Lian-Fu

Communications in Theoretical Physics

Abstract （711）

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We investigate the self-trapping of a Bose Josephson junction, which is dispersively coupled to a driven optical cavity. The cavity-induced nonlinearity is presented analytically, and its effect results in the appearance of the self-trapping for the Bose-Einstein condensates in the Josephson oscillation regime. In addition, there exists competition between the nonlinearities
induced by the interatomic interaction and by the driven cavity for the emergences of self-trapping. Our results show that the driven cavity can be utilized as a possible tool to produce the self-trapping for the condensates with weak interatomic interaction.

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A New Solution with Torsion in Model of dS Gauge Theory of Gravity

HUANG Chao-Guang and MA Meng-Sen,

Communications in Theoretical Physics

Abstract （638）

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A new static de Sitter solution with torsion in the model of de Sitter gauge theory of gravity is obtained. The torsion only contains O(3)-symmetric tensor part according to irreducible decomposition. Some properties of the new solution are discussed.

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Time-Machine Solutions of Einstein's Equations with Electromagnetic Field

SHEN Ming and SUN Qing-You

Communications in Theoretical Physics

Abstract （672）

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In this paper we investigate the time-machine problem in the electromagnetic field. Based on a metric which is a more general form of Ori's, we solve the Einstein's equations with the energy-momentum tensors for electromagnetic field, and construct the time-machine solutions, which solve the time machine problem in electromagnetic field.

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Entropy Corrections for a Charged Black Hole of String Theory

Alexis Larranaga

Communications in Theoretical Physics

Abstract （623）

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We study the entropy of the Gibbons-Maeda-Garfinkle-Horowitz-Strominger
(GMGHS) charged black hole, originated from the effective action that
emerges in the low-energy of string theory, beyond semiclassical approximations. Applying the properties of exact differentials for three variables to the first law thermodynamics we derive the quantum corrections
to the entropy of the black hole. The leading (logarithmic) and non leading corrections to the area law are obtained.

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Thermodynamics of DBI Black Holes in Anti-de Sitter Spacetime

JIA Dong-Yan, YUE Rui-Hong, and HUANG Shi-Ming

Communications in Theoretical Physics

Abstract （715）

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Through the gauge field theory, we obtain the solution of the DBI-AdS black hole. In the meantime, according to the relations between the action and the grand partition function, we obtain the grand partition function in the DBI-AdS black hole. The temperature and the potential of the DBI-AdS black hole are gained from differential of the grand partition function. With the thermodynamic relations, other thermodynamics are also obtained. The solution and the thermodynamics of the DBI-AdS black hole are turned out that they can reduce to the case of a charged black hole in four-dimensional spacetimes.

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An Anyon Model in a Toric Honeycomb Lattice

LIANG Long and YU Yue

Communications in Theoretical Physics

Abstract （666）

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We study an anyon model in a toric honeycomb lattice. The ground states and the low-lying excitations coincide with those of Kitaev toric code model and then the excitations obey mutual semionic statistics. This model is helpful to understand the toric code of anyons in a more symmetric way. On the other hand, there is a direct relation between this toric honeycomb model and a boundary coupled Ising chain array in a square lattice via Jordan-Wigner
transformation. We discuss the equivalence between these two models
in the low-lying sector and realize these anyon excitations in a conventional fermion system. The analysis for the ground state degeneracy in the last section can also be thought of as a complementarity of our previous work [Phys. A: Math. Theor. 43 (2010) 105306].

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Special Bi-Solitons for Asymmetric Nizhnik-Novikov-Veselov Equation

Lü Zhuo-Sheng

Communications in Theoretical Physics

Abstract （621）

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Employing a constructive algorithm and the symbolic computation,
we obtain a new explicit bi-soliton-like solution of the asymmetric
Nizhnik-Novikov-Veselov equation. The solution contains two arbitrary
functions which indicates that it can model various bi-soliton-like waves. In particular, specially choosing the arbitrary functions, we find some interesting bi-solitons with special shapes, which possess the traveling property of the traditional bi-solitons. We show the evolution of such bi-solitons by figures.

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Self-Organized Criticality Analysis of Earthquake Model Based onHeterogeneous Networks

WANG Lin, ZHANG Gui-Qing, and CHEN Tian-Lun

Communications in Theoretical Physics

Abstract （644）

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The original Olami-Feder-Christensen (OFC) model, which displays a robust power-law behavior, is a quasistatic two-dimensional version of the Burridge--Knopoff spring-block model of earthquakes. In this paper, we introduce a modified OFC model based on heterogeneous network, improving the redistribution rule of the original model. It can be seen as a generalization of the original OFC model. We numerically investigate the influence of the
parameters θ and β, which respectively control the intensity of the evolutive
mechanism of the topological growth and the inner selection dynamics
in our networks, and find that there are two distinct phases in the
parameter space (θ, β). Meanwhile, we study the influence of the control parameter a either. Increasing a, the earthquake behavior of the model transfers from local to global.

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Traffic Congestion Mechanism in Two Ramp Systems

ZHAO Xiao-Mei, SONG Gui-Cui, and SONG Yu-Kun

Communications in Theoretical Physics

Abstract （655）

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The aim of this paper is to study traffic properties in an on/off-ramp system with a bus stop close to the on/off ramp. The location of the bus stop in the on/off-ramp (thereafter downstream or upstream case) is discussed. The simulation results show that in the two ramp systems, the reasons for traffic congestions are different. In the on-ramp system, buses and cars coming from on-ramp interweave each other, while in the off-ramp system, buses
interweave with cars exiting to off-ramp. Thus, in the on-ramp (off-ramp) system, the upstream (downstream) bus stop is helpful to reduce the interweaving situation. Moreover, the negative effect will disappear when the distance between the bus stop and the on/off-ramp is more than 20 cells (i.e. 150 m). These qualitative findings may provide some suggestions on traffic management and optimization.

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Shape of Compact Toroidal Dimensions Tdθ and Casimir Effect on MD×Tdθ Spacetime

V.K. Oikonomou

Communications in Theoretical Physics

Abstract （680）

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We study the influence of the shape of compact dimensions to the Casimir energy and Casimir force of a scalar field. We examine both the massive and the massless scalar field. The total spacetime topology is M^D× T²_θ, where M^D is the D-dimensional Minkowski spacetime and T²_θ the twisted torus described by R₁, R₂, and θ. For the case R₁=R₂ we found that the massive bulk scalar field Casimir energy is singular for D=even and this singularity is
R-dependent and remains even when the force is calculated. Also
the massless Casimir energy and force is regular only for D=4 (!). This is very interesting phenomenologically. We examine the energy and force as a function of θ. Also we address the stabilization problem of the compact space. We also briefly discuss some phenomenological implications.

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Noether Symmetry and Noether Conserved Quantity of Nielsen Equation for Dynamical Systems of Relative Motion

XIE Yin-Li, YANG Xin-Fang, and JIA Li-Qun

Communications in Theoretical Physics

Abstract （646）

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Noether symmetry of Nielsen equation and Noether conserved quantity
deduced directly from Noether symmetry for dynamical systems of the relative motion are studied. The definition and criteria of Noether symmetry of a Nielsen equation under the infinitesimal transformations of groups are given. Expression of Noether conserved quantity deduced directly from Noether symmetry of Nielsen equation for the system are obtained. Finally, an example is given to illustrate the application of the results.

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Resonances-Excitation Calculation Studies Investigation of δ(3,3) in Ground State of 90Zr Cold Finite Heavy Nucleus at Equilibrium and Under Large Compression

Mohammed H.E. Abu-Sei'leek

Communications in Theoretical Physics

Abstract （681）

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A non-relativistic microscopic mean field theory of finite nuclei is investigated where the nucleus is described as a collection of nucleons and delta resonances. The ground state properties of ⁹⁰Zr nucleus have been
investigated at equilibrium and large amplitude compression using a
realistic effective baryon-baryon Hamiltonian based on Reid Soft Core (RSC)
potential. The sensitivity of the ground state properties is studied, such
as binding energy, nuclear radius, radial density distribution, and single
particle energies to the degree of compression. It is found that the most
of increasing in the nuclear energy generated under compression is used to
create the massive δ particles. For ⁹⁰Zr nucleus under compression at 2.5 times density of the normal nuclear density, the excited nucleons to δ's are increased sharply up to 14% of the total number of constituents. This result is consistent with the values extracted from relativistic heavy-ion collisions. The single particle energy levels are calculated and their behaviors under compression are examined too. A good agreement between results with effective Hamiltonian and the
phenomenological shell model for the low lying single-particle spectra is
obtained. A considerable reduction in compressibility for the nucleus, and
softening of the equation of state with the inclusion of the $\Delta $'s in
the nuclear dynamics are suggested by the results.

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Chiral Magnetic Effect and Chiral Phase Transition

FU Wei-Jie, LIU Yu-Xin,, and WU Yue-Liang

Communications in Theoretical Physics

Abstract （654）

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We study the influence of the chiral phase transition on the chiral magnetic effect. The azimuthal charge-particle correlations as functions of the temperature are calculated. It is found that there is a pronounced cusp in the correlations as the temperature reaches its critical value for the QCD phase transition. It is predicted that there will be a drastic suppression of the charge-particle correlations as the collision energy in RHIC decreases to below a critical value. We show then the azimuthal charge-particle correlations can be the signal to identify the occurrence of the QCD phase transitions in RHIC energy scan experiments.

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Generation of Broadband Attosecond Pulse via Controlling Quantum Path by Two Color Field in Long Wavelength Driving Regime

LUO Jiang-Hua

Communications in Theoretical Physics

Abstract （679）

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In this paper, we have investigated theoretically the high harmonic generation form helium atom in long wavelength driving regime at
2000 nm through solving time-dependent Schrödinger equation. By adding a
second harmonic pulse (1000~nm) and a UV attosecond pulse (200 nm) to the driving field, an efficient method for picking out and enhancing ionization
path to generate high-yield supercontinuum harmonics is realized, and then
an isolated sub-100 as pulse with a bandwidth of 190 eV is significantly obtained.

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Controllable Absorption and Dispersion Properties of an RF-drivenFive-Level Atom in a Double-Band Photonic-Band-Gap Material

DING Chun-Ling, LI Jia-Hua, and YANG Xiao-Xue

Communications in Theoretical Physics

Abstract （714）

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The probe absorption-dispersion spectra of a radio-frequency (RF)-driven five-level atom embedded in a photonic crystal are investigated by considering the isotropic double-band photonic-band-gap (PBG) reservoir. In the model used, the two transitions are, respectively, coupled by the upper and lower bands
in such a PBG material, thus leading to some curious phenomena. Numerical simulations are performed for the optical spectra. It is found that when one transition frequency is inside the band gap and the other is outside the gap, there emerge three peaks in the absorption spectra. However, for the case that two transition frequencies lie inside or outside the band gap, the spectra display four absorption profiles. Especially, there appear two sharp peaks
in the spectra when both transition frequencies exist inside the band gap. The influences of the intensity and frequency of the RF-driven field on the absorptive and dispersive response are analyzed under different band-edge positions. It is found that a transparency window appears in the absorption spectra and is accompanied by a very steep variation of the dispersion profile by adjusting system parameters. These results show that the absorption-dispersion properties of the system depend strongly on the RF-induced quantum interference and the density of states (DOS) of the PBG reservoir.

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Dust Acoustic Solitary Waves in Saturn F-ring's Region

E.K. El-Shewy, M.I. Abo el Maaty, H.G. Abdelwahed, and M.A. Elmessary

Communications in Theoretical Physics

Abstract （689）

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Effect of hot and cold dust charge on the
propagation of dust-acoustic waves
(DAWs) in unmagnetized plasma having electrons, singly charged ions, hot and
cold dust grains has been investigated. The reductive perturbation method
is employed to reduce the basic set of fluid equations to the Kortewege-de
Vries (KdV) equation. At the critical hot dusty plasma density N_h0, the
KdV equation is not appropriate for describing the system. Hence, a set of
stretched coordinates is considered to derive the modified KdV equation. It
is found that the presence of hot and cold dust charge grains not only
significantly modifies the basic properties of solitary structure, but also
changes the polarity of the solitary profiles. In the vicinity of the critical hot dusty plasma density N_h0, neither KdV nor mKdV equation is appropriate for describing the DAWs. Therefore, a further modified KdV (fmKdV) equation is derived, which admits both soliton and double layer solutions.

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Shocks and Solitons in Ultradense Degenerate Electron-Positron-Ion Plasmas

S.A. Khan and Arshad M. Mirza

Communications in Theoretical Physics

Abstract （587）

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The formation and propagation of shocks and solitons are investigated in an
unmagnetized, ultradense plasma containing degenerate Fermi gas of electrons and positrons, and classical ion gas by employing Thomas-Fermi model. For this purpose, a deformed Korteweg-de Vries-Berger (dKdVB) equation is derived using the reductive perturbative technique for cold, adiabatic, and isothermal ions. Localized analytical solutions of dKdVB equation in planar geometry are obtained for dispersion as well as dissipation dominant cases. For nonplanar (cylindrical and spherical) geometry, time varying numerical shock wave solution of dKdVB equation is found. Its dispersion dominant case leading to the soliton solution is also discussed. The effect of ion temperature, positron concentration and dissipation is found significant on these nonlinear structures. The relevance of the results to the systems of scientific interest is pointed out.

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Electronic Transport Calculations Using Maximally-Localized WannierFunctions

WANG Neng-Ping

Communications in Theoretical Physics

Abstract （673）

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I present a method to calculate the ballistic transport properties of atomic-scale structures under bias. The electronic structure of the system is calculated using the Kohn-Sham scheme of density functional theory (DFT). The DFT eigenvectors are then transformed into a set of maximally localized Wannier functions (MLWFs) [N. Marzari and D. Vanderbilt, Phys. Rev. B 56 (1997) 12847]. The MLWFs are used as a minimal basis set to obtain the Hamitonian matrices of the scattering region and the adjacent leads,
which are needed for transport calculation using the nonequilibrium Green's function formalism. The coupling of the scattering region to the semi-infinite leads is described by the self-energies of the leads. Using the nonequilibrium Green's function method, one calculates self-consistently the charge distribution of the system under bias and evaluates the transmission and current through the system. To solve the Poisson equation within the scheme of MLWFs I introduce a computationally efficient method. The method is applied to a molecular hydrogen contact in two transition metal monatomic wires (Cu and Pt). It is found that for Pt the I-V characteristics is approximately linear dependence, however, for Cu the I-V characteristics manifests a linear dependence at low bias voltages and exhibits apparent nonlinearity at higher bias voltages. I have also calculated the transmission in the zero bias voltage limit for a single CO molecule adsorbed on Cu and Pt monatomic wires. While a chemical scissor effect occurs for the Cu monatomic wire with an adsorbed CO molecule, it is absent for the Pt monatomic wire due to the contribution of d-orbitals at the Fermi energy.

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Tunneling Conductance in a Normal Metal/Ferromagnetic SuperconductorNano-Junction at a Finite Temperature

Hamidreza Emamipour and M.R. Abolhassani

Communications in Theoretical Physics

Abstract （719）

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In this study, we investigate the tunneling conductance at a finite temperature in a normal metal/ferromagnetic superconductor nano-junction where the ferromagnetic superconductor (FS) is in three different cooper pairing states: spin singlet s-wave pairing (SWP), spin triplet opposite spin pairing (OSP), and spin triplet equal spin pairing (ESP) while including Fermi
wave mismatch (FWM) and effective mass mismatch (EMM) in two sides of the nano-junction. We find that the conductance shows clearly different behaviors all depending on the symmetries of cooper pairing in a manner
that the conductance spectra shows a gap-like structure, two interior dips
structure and zero bias peak for SWP, OSP, and ESP, respectively. Also, the
effective FS gap (δ_eff) is a linear and decreasing function of exchange field. The slope of (δ_eff) versus exchange field for OSP is twice the SWP. Thus, we can determine the spin polarization of N/FS nano-junction based on the dependence of (δ_eff) to exchange field.

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Phonon States and Dispersive Spectra of Polar Optical Phonons inQuasi-One-Dimensional Nanowires of Wurtzite ZnO and Zinc-Blend MgO Semiconductors

ZHANG Li

Communications in Theoretical Physics

Abstract （670）

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Within the framework of the macroscopic dielectric continuum model and Loudon's uniaxial crystal model, the phonon modes of a wurtzite/zinc-blende one-dimensional (1D) cylindrical nanowire (NW) are derived and studied. The analytical phonon states of phonon modes are given. It is found that there exist two types of polar phonon modes, i.e. interface optical (IO) phonon modes and the quasi-confined (QC) phonon modes existing in 1D wurtzite/zinc-blende NWs. Via the standard procedure of field quantization, the Fröhlich electron-phonon interaction Hamiltonians are obtained. Numerical calculations of dispersive behavior of these phonon modes on a wurtzite/zinc-blende ZnO/MgO NW are performed. The frequency ranges of the IO and QC phonon modes of the ZnO/MgO NWs are analyzed and discussed. It is found that the IO modes only exist in one frequency range, while QC modes may appear in three frequency ranges. The dispersive properties of the IO and QC modes on the free wave-number k_z and the azimuthal quantum number m are
discussed. The analytical Hamiltonians of electron-phonon interaction obtained here are quite useful for further investigating phonon influence on optoelectronics properties of wurtzite/zinc-blende 1D NW structures.

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Trajectory Control of Scale-Free Dynamical Networks with ExogenousDisturbances

YANG Hong-Yong, ZHANG Shun, and ZONG Guang-Deng

Communications in Theoretical Physics

Abstract （694）

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In this paper, the trajectory control of multi-agent dynamical systems with exogenous disturbances is studied. Suppose multiple agents composing of a scale-free network topology, the performance of rejecting disturbances for the low degree node and high degree node is analyzed. Firstly, the consensus of multi-agent systems without disturbances is studied by designing a pinning control strategy on a part of agents, where this pinning control can bring multiple agents' states to an expected consensus track. Then, the
influence of the disturbances is considered by developing disturbance observers, and disturbance observers based control (DOBC) are developed for disturbances generated by an exogenous system to estimate the disturbances. Asymptotical consensus of the multi-agent systems with disturbances under the composite controller can be achieved for scale-free network topology. Finally, by analyzing examples of multi-agent systems with scale-free network topology and exogenous disturbances, the verities of the results are proved. Under the DOBC with the designed parameters, the trajectory convergence of multi-agent systems is researched by pinning two class of the nodes. We have found that it has more stronger robustness to exogenous disturbances for the high degree node pinned than that of the low
degree node pinned.

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A General Formula of Flow Equations for Harry-Dym Hierarchy

CHENG Ji-Peng, HE Jing-Song, and WANG Li-Hong

Communications in Theoretical Physics

Abstract （662）

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In this paper, we derive a general formula of the flow equtions for the Harry-Dym hierarchy. And three applications in n-reduction, (2+1)-dimensional generalization, and Kupershmidt reduction, are considered.

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Recursion Operators of Two Supersymmetric Equations

LI Hong-Min, LI Biao, and LI Yu-Qi

Communications in Theoretical Physics

Abstract （632）

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From Lax representations, recursion operators for the supersymmetric KdV and the supersymmetric Kaup-Kupershimdt (SKK) equations are proposed explicitly. Under some special conditions, the recursion operator of the supersymmetric
Sawada-Kotera equation can be recovered by the one of the SKK equation.

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Exact Solutions of the Harry-Dym Equation

Reza Mokhtari

Communications in Theoretical Physics

Abstract （704）

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The aim of this paper is to generate exact travelling wave solutions of the Harry-Dym equation through the methods of Adomian decomposition, He's variational iteration, direct integration, and power series. We show that the two later methods are more successful than the two former to obtain more solutions of the equation.

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Two Types of Coupling Integrable Couplings of the S-mKdV Hierarchy

WEI Yuan and ZHANG Yu-Feng

Communications in Theoretical Physics

Abstract （688）

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Firstly 4 Lie algebras are constructed. Then applications of the loop algebra are presented to obtain two types of coupling integrable couplings of the S-mKdV hierarchy by using Tu scheme. The coupling integrable couplings
of the S-mKdV hierarchy obtained in the paper reduce to the coupling integrable couplings of the mKdV equation and the coupling integrable couplings of the nonlinear Schrödinger equation respectively. The method
given in the paper can be used to other hierarchies generally.

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A New Auto-Bäcklund Transformation and Two-Soliton Solution for(3+1)-Dimensional Jimbo-Miwa Equation

LIU Chun-Ping and ZHOU Ling

Communications in Theoretical Physics

Abstract （658）

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By improving the extended homogeneous balance method, a general method is suggested to derive a new auto-Bäcklund transformation (BT) for (3+1)-Dimensional Jimbo-Miwa (JM) equation. The auto-BT obtained by using our method only involves one quadratic homogeneity equation written as a bilinear equation. Based on the auto-BT, two-soliton solution of the (3+1)-Dimensional JM equation is obtained.

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Quantum Mechanical Correspondence of Poisson Integral Formula

FAN Hong-Yi and JIANG Nian Quan

Communications in Theoretical Physics

Abstract （778）

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In this paper we set up quantum mechanical correspondence of the Poisson
integral formula. We show that Poisson kernel function existing in the
transformation between the continuum entangled state representation and its induced state, i.e. the number-difference-correlated amplitude entangled
state representation.

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Quasinormal Modes of Phantom Scalar Perturbation in Background ofReissner-Nordström Black Hole

PAN Qi-Yuan and SU Ru-Keng

Communications in Theoretical Physics

Abstract （634）

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We have investigated the quasinormal modes (QNMs) of phantom scalar perturbation in a Reissner-Nordström (RN) background. We find that the dependence of QNMs on the mass of the field for the phantom perturbation is
totally different from that of usual massive perturbation. However, we obtain the same critical value of the overtone number for an angular quantum number from which the mass will begin to have a reverse effect on the real part of QNM frequencies and the perturbation-independent relation between the QNMs and the second order thermodynamic phase transition.

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q-Deformed Entangled States Representations and Some Applications

XU Ye-Jun,, SONG Jun, YUAN Hong-Cun, and LIU Qiu-Yu

Communications in Theoretical Physics

Abstract （627）

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The q-deformed entangled states are introduced by using deformation quantization methods and new normal ordering of the vacuum projection operator for $q$-deformed boson oscillator. In similar way, by virtue of the technique of integration within an ordered product (IWOP) of operators, the new completeness and orthogonality relations composed of the bra and ket, which are not mutually Hermitian conjugates are obtained. Furthermore, the
property of squeezing operator represented by the q-deformed entangled states is exhibited. Lastly, the nonclassical properties of the q-deformed two-mode squeezed vacuum state are studied.

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