中国物理B ›› 2009, Vol. 18 ›› Issue (11): 4726-4733.doi: 10.1088/1674-1056/18/11/020

• • 上一篇    下一篇

Effects of periodic optical lattice potential on dark solitons in a Bose Einstein condensate

王东宁1, 李宏2   

  1. (1)Department of Electrical Engineering, Hong Kong Polytechnic University, Hong Kong, China; (2)School of Physics and Electronic Science, Hubei Normal University, Huangshi 435002, China;School of Mechanical and Electronic Engineering, Huangshi Institute of Technology, Huangshi 435003, China
  • 收稿日期:2009-03-18 修回日期:2009-03-31 出版日期:2009-11-20 发布日期:2009-11-20
  • 基金资助:
    Project supported by the Research Program of the Hong Kong Polytechnic University (Grant No A-PA2Q) and the Scientific and Technological Research Program of Education Department of Hubei Province, China (Grant No Z200722001).

Effects of periodic optical lattice potential on dark solitons in a Bose--Einstein condensate

Li Hong(李宏)a)b)† and Wang Dong-Ning(王东宁)c)   

  1. a School of Physics and Electronic Science, Hubei Normal University, Huangshi 435002, China; b School of Mechanical and Electronic Engineering, Huangshi Institute of Technology, Huangshi 435003, China; c Department of Electrical Engineering, Hong Kong Polytechnic University, Hong Kong, China
  • Received:2009-03-18 Revised:2009-03-31 Online:2009-11-20 Published:2009-11-20
  • Supported by:
    Project supported by the Research Program of the Hong Kong Polytechnic University (Grant No A-PA2Q) and the Scientific and Technological Research Program of Education Department of Hubei Province, China (Grant No Z200722001).

摘要: This paper investigates the dynamics of dark solitons in a Bose--Einstein condensate with a magnetic trap and an optical lattice (OL) trap, and analyses the effects of the periodic OL potential on the dynamics by applying the variational approach based on the renormalized integrals of motion. The results show that the dark soliton becomes only a standing-wave and free propagation of the dark soliton is not possible when the periodic length of the OL potential is approximately equal to the effective width of the dark soliton. When the periodic length is very small or very large, the effects of the OL potential on the dark soliton will be sharply reduced. Finally, the numerical results confirm these theoretical findings.

Abstract: This paper investigates the dynamics of dark solitons in a Bose--Einstein condensate with a magnetic trap and an optical lattice (OL) trap, and analyses the effects of the periodic OL potential on the dynamics by applying the variational approach based on the renormalized integrals of motion. The results show that the dark soliton becomes only a standing-wave and free propagation of the dark soliton is not possible when the periodic length of the OL potential is approximately equal to the effective width of the dark soliton. When the periodic length is very small or very large, the effects of the OL potential on the dark soliton will be sharply reduced. Finally, the numerical results confirm these theoretical findings.

Key words: Bose--Einstein condensate, dark soliton, magnetic potential, optical lattice potential

中图分类号:  (Tunneling, Josephson effect, Bose-Einstein condensates in periodic potentials, solitons, vortices, and topological excitations)

  • 03.75.Lm
37.10.De (Atom cooling methods)