Please use this identifier to cite or link to this item: http://scholarbank.nus.edu.sg/handle/10635/104768
Title: Dynamics of the ground state and central vortex states in Bose-Einstein condensation
Authors: Bao, W. 
Zhang, Y.
Keywords: Bose-Einstein condensation
Central vortex state
Gross-Pitaevskii equation
Ground state
Time-splitting sine-pseudospectral method
Variance identity
Issue Date: Dec-2005
Citation: Bao, W.,Zhang, Y. (2005-12). Dynamics of the ground state and central vortex states in Bose-Einstein condensation. Mathematical Models and Methods in Applied Sciences 15 (12) : 1863-1896. ScholarBank@NUS Repository.
Abstract: In this paper, we study dynamics of the ground state and central vortex states in Bose-Einstein condensation (BEC) analytically and numerically. We show how to define the energy of the Thomas-Fermi (TF) approximation, prove that the ground state is a global minimizer of the energy functional over the unit sphere and all excited states are saddle points in linear case, derive a second-order ordinary differential equation (ODE) which shows that time-evolution of the condensate width is a periodic function with/without a perturbation by using the variance identity, prove that the angular momentum expectation is conserved in two dimensions (2D) with a radial symmetric trap and 3D with a cylindrical symmetric trap for any initial data, and study numerically stability of central vortex states as well as interaction between a few central vortices with winding numbers ±1 by a fourth-order time-splitting sine-pseudospectral (TSSP) method. The merit of the numerical method is that it is explicit, unconditionally stable, time reversible and time transverse invariant. Moreover, it conserves the position density, performs spectral accuracy for spatial derivatives and fourth-order accuracy for time derivative, and possesses "optimal" spatial/temporal resolution in the semiclassical regime. Finally we find numerically the critical angular frequency for single vortex cycling from the ground state under a far-blue detuned Gaussian laser stirrer in strong repulsive interaction regime and compare our numerical results with those in the literatures. © World Scientific Publishing Company.
Source Title: Mathematical Models and Methods in Applied Sciences
URI: http://scholarbank.nus.edu.sg/handle/10635/104768
ISSN: 02182025
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

Page view(s)

42
checked on Nov 2, 2018

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.