Numerical simulation of nonequilibrium states in a trapped Bose-Einstein condensate

23rd International Laser Physics Workshop

Novikov, A.N.^1,2 ; Yukalov, V.I.^1,2 ; Bagnato, V.S.^2

Bogolubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna

141980, Russia^1

Instituto de Fisica de São Carlos, Universidade de São Paulo, CP 369, São Carlos, São Paulo

13560-970, Brazil^2

关键词: Bose-condensed systems;    Bose-Einstein condensates;    Excitation amplitudes;    Non equilibrium;    Nonequilibrium state;    Spatial structure;    Split-step Fourier transform method;    Trapped condensates;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/594/1/012040/pdf
DOI  :  10.1088/1742-6596/594/1/012040

来源: IOP

【 摘 要 】

In this work we present numerical study of a trapped Bose-Einstein condensate perturbed by an alternating potential. The relevant physical situation has been recently realized in experiment, where the trapped condensate of87Rb, being strongly perturbed, exhibits the set of spatial structures. Firstly, regular vortices are detected. Further, increasing either the excitation amplitude or modulation time results in the transition to quantum vortex turbulence, followed by a granular state. Numerical simulation of the nonequilibrium Bose-condensed system is based on the solution of the time-dependent 3D nonlinear Schrodinger equation within the static and dynamical algorithms. The damped gradient step and time split-step Fourier transform methods are employed. We demonstrate that computer simulations qualitatively reproduce the experimental picture, and describe well the main experimental observables.