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arXiv · 1610.09076

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

Gavriil Shchedrin·Daniel Jaschke·Lincoln D. Carr
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Abstract

We explore 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 non-zero 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.

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Gavriil Shchedrin, Daniel Jaschke, Lincoln D. Carr. 2016-10-28. Damping-free collective oscillations of a driven two-component Bose gas in optical lattices. https://doi.org/10.1103/physreva.97.043601

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