Damping-free collective oscillations of a driven two-component Bose gas in optical lattices

作者:Shchedrin Gavriil*; Jaschke Daniel; Carr Lincoln D
来源:PHYSICAL REVIEW A, 2018, 97(4): 043601.
DOI:10.1103/PhysRevA.97.043601

摘要

We explore the quantum many-body physics of a driven Bose-Einstein condensate in optical lattices. The laser field induces a gap in the generalized Bogoliubov spectrum proportional to the effective Rabi frequency. The lowest-lying modes in a driven condensate are characterized by zero group velocity and nonzero current. Thus, the laser field induces roton modes, which carry interaction in a driven condensate. We show that collective excitations below the energy of the laser-induced gap remain undamped, while above the gap they are characterized by a significantly suppressed Landau damping rate.

  • 出版日期2018-4-2

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