Eur. Phys. J. D 20, 117-119 (2002)
https://doi.org/10.1140/epjd/e2002-00112-5

Low energy excitations of a quasi-2D Bose-Einstein condensate

¹ CCAST (World Lab.), P.O. Box 8730, Beijing 100080, P.R. China
² Department of physics, Lanzhou University, Lanzhou 730000, P.R. China

Corresponding author: ^a wangzc@lzu.edu.cn

Received: 31 October 2001
Revised: 1 March 2002
Published online: 28 June 2002

Abstract

Starting from the Gross-Pitaevskii energy functional of the 3D Bose-Einstein Condensate, we derive approximately the energy functional and the effective coupling constant of the quasi-2D condensate. The evolution of the quasi-2D condensate wave function is studied by a variational method. Low energy excitation spectra for both positive and negative scattering lengths are analyzed. The condition of collapse instability of a quasi-2D Bose gas with attractive particle interaction is also proposed.