中国物理B ›› 2024, Vol. 33 ›› Issue (2): 20314-020314.doi: 10.1088/1674-1056/ad1179

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Dynamical nonlinear excitations induced by interaction quench in a two-dimensional box-trapped Bose-Einstein condensate

Zhen-Xia Niu(牛真霞)1 and Chao Gao(高超)1,2,†   

  1. 1 Department of Physics, Zhejiang Normal University, Jinhua 321004, China;
    2 Key Laboratory of Optical Information Detection and Display Technology of Zhejiang, Zhejiang Normal University, Jinhua 321004, China
  • 收稿日期:2023-10-03 修回日期:2023-11-20 接受日期:2023-12-01 出版日期:2024-01-16 发布日期:2024-01-19
  • 通讯作者: Chao Gao E-mail:gaochao@zjnu.edu.cn
  • 基金资助:
    Project supported by the Natural Science Foundation of Zhejiang Province of China (Grant Nos. LQ22A040006, LY21A040004, LR22A040001, and LZ21A040001) and the National Natural Science Foundation of China (Grant Nos. 11835011 and 12074342).

Dynamical nonlinear excitations induced by interaction quench in a two-dimensional box-trapped Bose-Einstein condensate

Zhen-Xia Niu(牛真霞)1 and Chao Gao(高超)1,2,†   

  1. 1 Department of Physics, Zhejiang Normal University, Jinhua 321004, China;
    2 Key Laboratory of Optical Information Detection and Display Technology of Zhejiang, Zhejiang Normal University, Jinhua 321004, China
  • Received:2023-10-03 Revised:2023-11-20 Accepted:2023-12-01 Online:2024-01-16 Published:2024-01-19
  • Contact: Chao Gao E-mail:gaochao@zjnu.edu.cn
  • Supported by:
    Project supported by the Natural Science Foundation of Zhejiang Province of China (Grant Nos. LQ22A040006, LY21A040004, LR22A040001, and LZ21A040001) and the National Natural Science Foundation of China (Grant Nos. 11835011 and 12074342).

摘要: Manipulating nonlinear excitations, including solitons and vortices, is an essential topic in quantum many-body physics. A new progress in this direction is a protocol proposed in [Phys. Rev. Res. 2 043256 (2020)] to produce dark solitons in a one-dimensional atomic Bose-Einstein condensate (BEC) by quenching inter-atomic interaction. Motivated by this work, we generalize the protocol to a two-dimensional BEC and investigate the generic scenario of its post-quench dynamics. For an isotropic disk trap with a hard-wall boundary, we find that successive inward-moving ring dark solitons (RDSs) can be induced from the edge, and the number of RDSs can be controlled by tuning the ratio of the after- and before-quench interaction strength across different critical values. The role of the quench played on the profiles of the density, phase, and sound velocity is also investigated. Due to the snake instability, the RDSs then become vortex-antivortex pairs with peculiar dynamics managed by the initial density and the after-quench interaction. By tuning the geometry of the box traps, demonstrated as polygonal ones, more subtle dynamics of solitons and vortices are enabled. Our proposed protocol and the discovered rich dynamical effects on nonlinear excitations can be realized in near future cold-atom experiments.

关键词: Bose-Einstein condensate, quench interaction, soliton, vortex

Abstract: Manipulating nonlinear excitations, including solitons and vortices, is an essential topic in quantum many-body physics. A new progress in this direction is a protocol proposed in [Phys. Rev. Res. 2 043256 (2020)] to produce dark solitons in a one-dimensional atomic Bose-Einstein condensate (BEC) by quenching inter-atomic interaction. Motivated by this work, we generalize the protocol to a two-dimensional BEC and investigate the generic scenario of its post-quench dynamics. For an isotropic disk trap with a hard-wall boundary, we find that successive inward-moving ring dark solitons (RDSs) can be induced from the edge, and the number of RDSs can be controlled by tuning the ratio of the after- and before-quench interaction strength across different critical values. The role of the quench played on the profiles of the density, phase, and sound velocity is also investigated. Due to the snake instability, the RDSs then become vortex-antivortex pairs with peculiar dynamics managed by the initial density and the after-quench interaction. By tuning the geometry of the box traps, demonstrated as polygonal ones, more subtle dynamics of solitons and vortices are enabled. Our proposed protocol and the discovered rich dynamical effects on nonlinear excitations can be realized in near future cold-atom experiments.

Key words: Bose-Einstein condensate, quench interaction, soliton, vortex

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

  • 03.75.Lm
47.35.Fg (Solitary waves) 47.32.C- (Vortex dynamics) 52.35.Mw (Nonlinear phenomena: waves, wave propagation, and other interactions (including parametric effects, mode coupling, ponderomotive effects, etc.))