The Institute of Applied Physics and Computational Mathematics was established in 1958 in Beijing in the People's Republic of China. The institution conducts research on nuclear warhead design computations for the Chinese Academy of Engineering Physics in Mianyang, Sichuan and focuses on applied theoretical research and on the study of fundamental theories. Its main research fields include: Theoretical Physics, Nuclear Fusion and Plasma Physics, Nuclear Physics and Atomic Molecular Physics, Laser Physics, Fluid Dynamics, Applied Mathematics, Computer Application, Computer Application, Arms Control Science and Technology. From August 2012, the director of the institute was LI Hua. Wikipedia.
Zhang W.,CAS Beijing Institute of Applied Physics And Computational Mathematics |
Govorov A.O.,Ohio University
Physical Review B - Condensed Matter and Materials Physics | Year: 2011
We develop a quantum theory of the field-tunable nonlinear Fano effect in the hybrid metal-semiconductor nanostructures, in which the plasmon (semicontinuous collective intraband excitation) and the exciton (discrete single-particle interband excitation) are treated on the same footing. Our quantum theory shows that the quantum interference due to the plasmon-exciton interaction leads to the nonlinear Fano effect described by a generalized complex field-tunable Fano factor for the systems with strong external field and dephasing. We establish the relation between quantum and semiclassical theories and show that the results of the quantum and semiclassical theories differ both qualitatively and quantitatively in the strongly nonlinear regime-in particular, the quantum theory predicts the absence of nonlinear instability in the hybrid systems with plasmon relaxation. © 2011 American Physical Society.
Jiang F.,CAS Beijing Institute of Applied Physics And Computational Mathematics
Nonlinear Analysis: Real World Applications | Year: 2011
In [A. Jngel, Global weak solutions to compressible NavierStokes equations for quantum fluids, SIAM J. Math. Anal. 42 (2010) 10251045], Jngel proved the global existence of the barotropic compressible quantum NavierStokes equations for when the viscosity constant is bigger than the scaled Planck constant. Recently, Dong [J. Dong, A note on barotropic compressible quantum NavierStokes equations, Nonlinear Anal. TMA 73 (2010) 854856] extended Jngel's result to the case where the viscosity constant is equal to the scaled Planck constant by using a new estimate of the square root of the solutions. In this paper we show that Jngel's existence result still holds when the viscosity constant is bigger than the scaled Planck constant. Consequently, with our result, the existence for all physically interesting cases of the scaled Planck and viscosity constants is obtained. © 2010 Elsevier Ltd. All rights reserved.
Chang L.,CAS Beijing Institute of Applied Physics And Computational Mathematics |
Luo S.,CAS Academy of Mathematics and Systems Science
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013
The geometric discord, as introduced by Dakić, Vedral, and Brukner, is a significant figure of merit for quantum correlations with wide applications. However, it has a curious drawback in that it may change reversibly by trivially adding a local ancilla, as recently criticized by Piani. This casts doubt on the information content and usage of geometric discord. In this work, we show that this problem with geometric discord can be remedied simply by starting from the square root of a density operator, rather than the density operator itself, in defining the discord. Moreover, most other basic properties and analytical aspects of the original geometric discord can be carried over to this modified discord. Due to the square-root character, which is reminiscent of probability amplitudes ubiquitous in quantum theory, the modified discord seems to capture quantum correlations in a more intrinsic and informational fashion. © 2013 American Physical Society.
Zhao L.-C.,CAS Beijing Institute of Applied Physics And Computational Mathematics |
Zhao L.-C.,Hefei University of Technology
Annals of Physics | Year: 2013
We study rogue waves of Bose-Einstein condensate (BEC) analytically in a time-dependent harmonic trap with a complex potential. Properties of the nonautonomous rogue waves are investigated analytically. It is reported that there are possibilities to 'catch' rogue waves through manipulating nonlinear interaction properly. The results provide many possibilities to manipulate rogue waves experimentally in a BEC system. © 2012 Elsevier Inc.
Chang L.,CAS Beijing Institute of Applied Physics And Computational Mathematics
Journal of Computational Physics | Year: 2014
A new reconstruction algorithm is developed to obtain diffusion schemes with cell-centered unknowns only. The main characteristic of the new algorithm is the flexibility of stencils when the auxiliary unknowns are reconstructed with cell-centered unknowns. The stencils are selected depending on the mesh geometry and discontinuities of diffusion coefficients. Moreover, an explicit expression is derived for interpolating the auxiliary unknowns in terms of cell-centered unknowns, and the auxiliary unknowns can be defined at any point on the edge. The algorithm is applied to construct several new diffusion schemes, whose effectiveness is illustrated by numerical experiments. For anisotropic problems with or without discontinuities, nearly second order accuracy is achieved on skewed meshes. © 2013 Elsevier Inc.