Hu, Ying, Liang, Zhaoxin, Hu, Bambi
We investigate a Bose-Einstein condensate trapped in a 2D optical lattice in the presence of weak disorder within the framework of the Bogoliubov theory. In particular, we analyze the combined...
Power-dependent soliton steering in thermal nonlinear media (2009)
Ye, Fangwei, Kartashov, Yaroslav V., Hu, Bambi, Torner, Lluis
We address the existence and properties of optical solitons excited in thermal nonlinear media with a transverse refractive index gradient. We show that in such a geometry one can generate...
Ballistic Thermal Transistor of Dielectric Four-terminal Nanostructures (2009)
We report a theoretical model for a thermal transistor in dielectric four-terminal nanostructures based on mesoscopic ballistic phonon transport, in which a steady thermal flow condition of system is...
Light bullets in Bessel optical lattices with spatially modulated nonlinearity (2009)
Ye, Fangwei, Kartashov, Yaroslav V., Hu, Bambi, Torner, Lluis
We address the stability of light bullets supported by Bessel optical lattices with out-of-phase modulation of the linear and nonlinear refractive indices. We show that spatial modulation of the...
Negative differential thermal resistance induced by ballistic transport (2009)
Zhong, Wei-Rong, Yang, Ping, Ai, Bao-Quan, Shao, Zhi-Gang, Hu, Bambi
Using nonequilibrium molecular-dynamics simulations, we study the temperature dependence of the negative differential thermal resistance that appears in two-segment Frenkel-Kontorova lattices. We...
Elliptic Vortices in Composite Mathieu Lattices (2009)
Ye, Fangwei, Mihalache, Dumitru, Hu, Bambi
We address the elliptically shaped vortex solitons in defocusing nonlinear media imprinted with a composite Mathieu lattice. Elliptic vortices feature anisotropic patterns both in intensity and...
High-order Harmonic Generation in a Time-integrated Quantum Transition Picture (2008)
Chen, Y. J., Liu, J., Hu, Bambi
We develop a numerical scheme to investigate the high-order harmonic generation (HHG) in intense laser-matter interactions. Tracing the time evolution of every electronic laser-field-free state, we...
Theory of the critical Casimir force for He-4 film (2008)
Biswas, Shyamal, Bhattacharjee, J. K., Samanta, Himadri S., Bhattacharyya, Saugata, Hu, Bambi
We present an analytic theory of critical Casimir force for He-4 film below and above the lambda point. We take complex critical fluctuations and calculate the critical Casimir force by a...
Length-dependent oscillations in the dc conductance of laser-driven quantum wires (2008)
Martinez, D. F., Molina, Rafael A., Hu, Bambi
9 pages, 5 figures.-- PACS nrs.: 73.21.Hb, 72.10.-d, 73.23.-b.
Length-dependent oscillations in the dc conductance of laser-driven quantum wires (2008)
Martinez, D.F., Molina, Rafael A., Hu, Bambi
9 pages, 5 figures.--PACS nrs.: 73.21.Hb; 72.10.-d; 73.23.-b
Buyukdagli, Sahin, Savin, Alexander V., Hu, Bambi
We propose a new method for computing the temperature dependence of the heat capacity in complex molecular systems. The proposed scheme is based on the use of the Langevin equation with low frequency...
Chen, Yanjun, Liu, Jie, Hu, Bambi
We investigate the orientation dependence of high-order harmonic generation (HHG) from H$_2^+$ with different internuclear distances irradiated by intense laser fields both numerically and...
Operating molecular transistors as heat pumps (2007)
We study heat transport in transistor-like devices composed of two reservoirs and a gate electrode, with a ballistic electronic one-dimensional system connected between the two reservoirs and...
Quantum Depletion of a Soliton Condensate (2006)
Huang, Guoxiang, Deng, L., Yan, Jiaren, Hu, Bambi
We present rigorous results on the diagonalization of Bogoliubov Hamilto- nian for a soliton condensate. Using the complete and orthonomalized set of eigenfunction for the Bogoliubov de Gennes...
Jie, Quanlin, Hu, Bambi, Dong, Guangjong
We investigate numerically the tunneling effect under influence of another particle in a double well system. Such influence from only one degree of freedom makes decoherence and quantum-classical...
Asymmetric Properties of Heat Conduction in a One-Dimensional Frenkel-Kontorova Model (2005)
Hu, Bambi, Yang, Lei, Zhang, Yong
In this Letter, we show numerically that the rectifying effect of heat flux in a one-dimensional two-segment Frenkel-Kontorova chain demonstrated in recent literature is merely available under the...
Modification to the pre-factor of the semiclassical propagator (2005)
Jie, Quanlin, Hu, Bambi, Li, Baowen
We modify the pre-factor of the semiclassical propagator to improve its efficiency in practical implementations. The new pre-factor represents the smooth portion of an orbit's contribution, and leads...
Landau-Zener tunneling with many-body quantum effects in crystals of molecular magnets (2004)
Fu, Li-Bin, Chen, Shi-Gang, Hu, Bambi
We present a quantum interpretation of the heights in hysteresis of $Fe_{8}$ molecule at lower temperatures by treating the crystal as an Ising spin system with the dipolar interaction between spins....
Polarization and decoherence in a two-component Bose-Einstein Condensate (2004)
Kuang, Le-Man, Li, Jin-Hui, Hu, Bambi
We theoretically investigate polarization properties of a two-component Bose-Einstein condensate (BEC) and influence of decoherence induced by environment on BEC polarization through introducing four...
Entanglement as a signature of quantum chaos (2003)
Wang, Xiaoguang, Ghose, Shohini, Sanders, Barry C, Hu, Bambi
We explore the dynamics of entanglement in classically chaotic systems by considering a multiqubit system that behaves collectively as a spin system obeying the dynamics of the quantum kicked top. In...
Heat conduction in one-dimensional Yukawa chains (2003)
Hu, Bambi, Li, Haibin, Xie, Bai-Song
Heat conduction in one-dimensional Yukawa chains is investigated. It is shown numerically that it has the abnormal heat conduction which is proportional to the system size. Effects of asymmetric...
Bipartite entanglement and localization of one-particle states (2003)
Li, Haibin, Wang, Xiaoguang, Hu, Bambi
We study bipartite entanglement in a general one-particle state, and find that the linear entropy, quantifying the bipartite entanglement, is directly connected to the paricitpation ratio,...
Mode entanglement of electrons in the one-dimensional Frenkel-Kontorova model (2003)
Wang, Xiaoguang, Li, Haibin, Hu, Bambi
We study the mode entanglement in the one-dimensional Frenkel-Kontorova model, and found that behaviors of quantum entanglement are distinct before and after the transition by breaking of...
Zhang, Hong, Hu, Bambi, Hu, Gang, Ouyang, Qi, Kurths, J.
Turbulence control in the two-dimensional complex Ginzburg-Landau equation is investigated. A new approach is proposed for the control purpose. In the presence of a small spiral wave seed initiation,...
Non-Kramers degeneracy and oscillatory tunnel splittings in the biaxial Spin System (2002)
We have investigated analytically quantum tunneling of large spin in the biaxial spin system with the magnetic field applied along the hard and medium anisotropy axes by using a purely...
Driven Dynamics: A Probable Photodriven Frenkel-Kontorova Model (2002)
In this study, we examine the dynamics of a one-dimensional Frenkel-Kontorova chain consisting of nanosize clusters (the ''particles'') and photochromic molecules (the ''bonds''), and being subjected...
Fringe Structure in the Phase-Space Dynamics of Atomic Stabilization in An Intense Field (2002)
Liu, Jie, Chen, Si-gang, Li, Baowen, Hu, Bambi
An analytical expression of a Floquet operator, which describes the evolution of a wave packet in combined atomic and an intense laser field,is obtained approximately in the stabilization regime....
Electronic properties of the 1D Frenkel-Kontorova model (2002)
Tong, Peiqing, Li, Baowen, Hu, Bambi
The energy spectra and quantum diffusion of an electron in a 1D incommensurate Frenkel-Kontorova (FK) model are studied numerically. We found that the spectral and dynamical properties of electron...
Finite thermal conductivity in 1D models having zero Lyapunov exponents (2002)
Li, Baowen, Wang, Lei, Hu, Bambi
Heat conduction in three types of 1D channels are studied. The channels consist of two parallel walls, right triangles as scattering obstacles, and noninteracting particles. The triangles are placed...
Nonlinear Modulation of Multi-Dimensional Lattice Waves (2001)
Huang, Guoxiang, Konotop, Vladimir V., Tam, Hon-Wah, Hu, Bambi
The equations governing weakly nonlinear modulations of $N$-dimensional lattices are considered using a quasi-discrete multiple-scale approach. It is found that the evolution of a short wave packet...
Can disorder induce a finite thermal conductivity in 1D lattices? (2001)
Li, Baowen, Zhao, Hong, Hu, Bambi
We study heat conduction in one dimensional mass disordered harmonic and anharmonic lattices. It is found that the thermal conductivity $\kappa$ of the disordered anharmonic lattice is finite at low...
Quantum Frenkel-Kontorova Model (2001)
This paper gives a review of our recent work on the quantum Frenkel-Kontorova model. Using the squeezed state theory and the quantum Monte Carlo method, we have studied the effects of quantum...
Reply to Dhar's comment on "Can disorder induce a finite thermal conductivity in 1D lattices" (2001)
Li, Baowen, Zhao, Hong, Hu, Bambi
In his comment, Dhar (cond-mat/0106349) claims that the existence and uniqueness of a nonequilibrium stationary state has been proved by Lebowitz et al. We should point out that our observation does...
Hu, Bambi, Li, Baowen, Zhao, Hong
In this paper, it is shown that a configuration modulated system described by the Frenkel-Kontorova model can be locked at an incommensurate phase when the quantum zero point energy is taken into...
Wang, Lei, Wang, Bing-Hong, Hu, Bambi
We propose and study a new one-dimensional traffic flow cellular automaton (CA) model of high speed vehicles with the Fukui-Ishibashi-type acceleration for all cars and the Nagel-Schreckenberg-type...
Fejer average and the short term behaviors of a wave packet in infinite square well (2000)
Liu, Quan-Hui, Qi, Wei-Hong, Fu, Li-Ping, Hu, Bambi
The first two period behaviors of a quantum wave packet in an infinite square well potential is studied. First, the short term behavior of expectation value of a quantity on an equally weighted wave...
Parametric Simultons in Nonlinear Lattices (2000)
Parametric simultaneous solitary wave (simulton) excitations are shown possible in nonlinear lattices. Taking a one-dimensional diatomic lattice with a cubic potential as an example we consider the...
Coherence resonance near blowout bifurcation in nonlinear dynamical systems (2000)
Previous studies have shown that noise can induce coherence resonance in some nonlinear dynamical systems close to a bifurcation of a periodic motion, such as in excitable systems. We demonstrate...
Nonlinear dynamical systems possessing an invariant subspace in the phase space and chaotic or stochastic motion within the subspace often display on-off intermittency close to the threshold of...
Tunneling Dynamics of Bose-Einstein Condensates with Feshbach Resonances (2000)
We study tunneling dynamics of atomic pairs in Bose-Einstein condensates with Feshbach resonances. It is shown that the tunneling of the atomic pairs depends on not only the tunneling coupling...
Quantum Tunneling and Quantum-Classical Transitions in Large Spin Systems (2000)
Hu, Bambi, Zhang, De-gang, Li, Bo-zang
We have studied quantum tunneling of large spins in a biaxial spin system and in a single-axial spin system with a transverse magnetic field. The asymptotically exact eigenvalues and eigenstates of...
Disturbance spreading in incommensurate and quasiperiodic systems (2000)
Hu, Bambi, Li, Baowen, Tong, Peiqing
The propagation of an initially localized excitation in one dimensional incommensurate, quasiperiodic and random systems is investigated numerically. It is discovered that the time evolution of...
Heat conduction in one dimensional nonintegrable systems (2000)
Hu, Bambi, Li, Baowen, Zhao, Hong
Two classes of 1D nonintegrable systems represented by the Fermi-Pasta-Ulam (FPU) model and the discrete $\phi^4$ model are studied to seek a generic mechanism of energy transport in microscopic...
We study the dynamics of a lattice of coupled nonidentical Fitz Hugh-Nagumo system subject to independent external noise. It is shown that these stochastic oscillators can lead to global...
Numerical accuracy of Bogomolny's semiclassical quantization scheme in quantum billiards (1999)
Hu, Bambi, Li, Baowen, Rouben, Daniel C
We use the semiclassical quantization scheme of Bogomolny to calculate eigenvalues of the Lima\c con quantum billiard corresponding to a conformal map of the circle billiard. We use the entire...
Ground state wavefunction of the quantum Frenkel-Kontorova model (1999)
The wavefunction of an incommensurate ground state for a one-dimensional discrete sine-Gordon model -- the Frenkel-Kontorova (FK) model -- at zero temperature is calculated by the quantum Monte Carlo...
Quantum chaos of a kicked particle in a 1D infinite square potential well (1999)
Li, Baowen, Liu, Jie, Gu, Yan, Hu, Bambi
We study quantum chaos in a non-KAM system, i.e. a kicked particle in a one-dimensional infinite square potential well. Within the perturbative regime the classical phase space displays stochastic...
Wave transmission, phonon localization and heat conduction of 1D Frenkel-Kontorova chain (1999)
Tong, Peiqing, Li, Baowen, Hu, Bambi
We study the transmission coefficient of a plane wave through a 1D finite quasi-periodic system -- the Frenkel-Kontorova (FK) model -- embedding in an infinite uniform harmonic chain. By varying the...
Wang, Bing-Hong, Kwong, Y. R., Hui, P. M., Hu, Bambi
Three cellular automaton (CA) models of increasing complexity are introduced to model driven diffusive systems related to the generalized Frenkel-Kontorova (FK) models recently proposed by Braun...
Phase slips and phase synchronization of coupled oscillators (1998)
Zheng, Zhigang, Hu, Gang, Hu, Bambi
The behaviors of coupled oscillators, each of which has periodic motion with random natural frequency in the absence of coupling, are investigated. Some novel collective phenomena are revealed. At...
Zheng, Zhigang, Hu, Bambi, Hu, Gang
Brownian motion of an array of harmonically coupled particles subject to a periodic substrate potential and driven by an external bias is investigated. In the linear response limit (small bias), the...
Critical Behavior of Period Doublings in Coupled Inverted Pendulums (1998)
We study the critical behaviors of period doublings in N (N=2,3,4,...) coupled inverted pendulums by varying the driving amplitude $A$ and the coupling strength $c$. It is found that the critical...
Nonadiabatic Geometric Phase and Hannay Angle: A Squeezed State Approach (1998)
Liu, Jie, Hu, Bambi, Li, Baowen
The geometric phases of the cyclic states of a generalized harmonic oscillator with nonadiabatic time-periodic parameters are discussed in the framework of squeezed state. A class of cyclic states...
Hasegawa, Hiroshi, Li, Baowen, Ma, Jian-Zhong, Hu, Bambi
We have computed the spectral number variances of an extended random matrix ensemble predicted by Guhr's supersymmetry formula, showing a non-monotone increase of the curves that arises from an...
Cantori and dynamical localization in the Bunimovich Stadium (1998)
Borgonovi, Fausto, Conti, Paolo, Rebuzzi, Daniela, Hu, Bambi, Li, Baowen
Classical and quantum properties of the Bunimovich stadium in the diffusive regime are reviewed. In particular, the quantum properties are directly investigated using an approximate quantum map....
Universal statistics of wave functions in chaotic and disordered systems (1998)
Hu, Bambi, Li, Baowen, Wang, Weng-ge
We study a new statistics of wave functions in several chaotic and disordered systems: the random matrix model, band random matrix model, the Lipkin model, chaotic quantum billiard and the 1D...
Statistical Study for Eigenfunctions of 1-dimensional Tight Binding Model (1998)
For energy eigenfunctions of 1-dimensional tight binding model, the distribution of ratio of their nearest components, denoted by f(p), gives information for their fluctuation properties. The shape...
Nonadiabatic geometric phase for the cyclic evolution of a time-dependent Hamiltonian system (1998)
Liu, Jie, Hu, Bambi, Li, Baowen
The geometric phases of the cyclic states of a generalized harmonic oscillator with nonadiabatic time-periodic parameters are discussed in the framework of squeezed state. It is shown that the cyclic...
Relevance of Chaos in Numerical Solutions of Quantum Billiards (1998)
Li, Baowen, Robnik, Marko, Hu, Bambi
In this paper we have tested several general numerical methods in solving the quantum billiards, such as the boundary integral method (BIM) and the plane wave decomposition method (PWDM). We...
Analytical Results For The Steady State Of Traffic Flow Models With Stochastic Delay (1998)
Wang, Bing-Hong, Wang, Lei, Hui, P. M., Hu, Bambi
Exact mean field equations are derived analytically to give the fundamental diagrams, i.e., the average speed - car density relations, for the Fukui-Ishibashi one-dimensional traffic flow cellular...
Squeezed state dynamics of kicked quantum systems (1998)
Hu, Bambi, Li, Baowen, Liu, Jie, Zhou, Ji-Lin
We study kicked quantum systems by using the squeezed state approach. Taking the kicked quantum harmonic oscillator as an example, we demonstrate that chaos in an underlying classical system can be...
The quantum Frenkel-Kontorova model: a squeezed state approach (1998)
Hu, Bambi, Li, Baowen, Zhang, Wei-Min
The squeezed state is used to study the one-dimensional quantum mechanical Frenkel Kontorova model. A set of coupled equations for the particle's expectation value and the fluctuations for the ground...
Resonant steps and spatiotemporal dynamics in the damped dc-driven Frenkel-Kontorova chain (1998)
Zheng, Zhigang, Hu, Bambi, Hu, Gang
Kink dynamics of the damped Frenkel-Kontorova (discrete sine-Gordon) chain driven by a constant external force are investigated. Resonant steplike transitions of the average velocity occur due to the...
Bifurcations and Transitions to Chaos in An Inverted Pendulum (1998)
We consider a parametrically forced pendulum with a vertically oscillating suspension point. It is well known that, as the amplitude of the vertical oscillation is increased, its inverted state...
Energy transport and correlation between two attractors connected by Fermi-Pasta-Ulam chain (1998)
Fillipov, Alexander, Hu, Bambi, Li, Baowen, Zeltser, Alexander
We study numerically time evolution of a system which consists of two attractors connected by Fermi-Pasta-Ulam (FPU) chain. It is found that after sufficiently long time there exits self-consistent...
Quantum fluctuations: Enhancement or suppression of chaos? (1998)
Hu, Bambi, Li, Baowen, Liu, Jie, Zhou, Ji-Lin
We have studied the effects of quantum fluctuations on dynamical behavior by using squeezed state approach. Our numerical results of the kicked harmonic oscillator demonstrate qualitatively and...
Plateau in Above-Threshold-Ionization Spectra and Chaotic Behavior in Rescattering Process (1998)
Liu, Jie, Chen, Shi-Gang, Hu, Bambi
An improved quasistatic model is used to describe the ionization process of atoms in intense linearly polarized fields. Numerical calculations of Above-Threshold-Ionization (ATI) energy spectra and...
Chaotic Behavior of a One-dimensional Model Atom in an Intense Field (1998)
Liu, Jie, Chen, Shi-Gang, Hu, Bambi
In this paper we describe the rescattering process in optical field ionization through a one-dimensional model, which improves the well-known quasistatic model by adding the smoothed Coulomb...
Spatiotemporal dynamics of discrete sine-Gordon lattices with sinusoidal couplings (1997)
Zheng, Zhigang, Hu, Bambi, Hu, Gang
The spatiotemporal dynamics of a damped sine-Gordon chain with sinusoidal nearest-neighbor couplings driven by a constant uniform force are discussed. The velocity characteristics of the chain versus...
Statistical analysis of scars in stadium billiard (1997)
In this paper, by using our improved plane wave decomposition method, we study the scars in the eigenfunctions of the stadium billiard from very low state to as high as about the one millionth state....
Heat conduction in one dimensional chains (1997)
Hu, Bambi, LI, Baowen, Zhao, Hong
We study numerically the thermal conductivity in several different one dimensional chains. We show that the phonon-lattice interaction is the main ingredient of the Fourier heat law. Our argument...
Asymmetric gap soliton modes in diatomic lattices with cubic and quartic nonlinearity (1997)
Nonlinear localized excitations in one-dimensional diatomic lattices with cubic and quartic nonlinearity are considered analytically by a quasi-discreteness approach. The criteria for the occurence...
Dynamical phase diagram of the dc-driven underdamped Frenkel-Kontorova chain (1997)
Paliy, Maxim, Braun, Oleg, Dauxois, Thierry, Hu, Bambi
Multistep dynamical phase transition from the locked to the running state of atoms in response to a dc external force is studied by MD simulations of the generalized Frenkel-Kontorova model in the...
Effects of a Magnetic Field on a Modulated Phase (1996)
The effects of a magnetic field on a modulated phase is studied. A modulated phase is found to have two critical fields $H_{1}$ and $H_{2}$. For a large enough magnetic field. $H_1$ can be...
A Frenkel-Kontorova Model with Two Spring Constants: New Phases and Phase Transitions (1996)
A discrete Frenkel-Kontorova model with two alternate spring constants $k_{1}$ and $k_{2}$ is studied. It is found that this model has many surprising behaviours. The continuum version of this model...