Collective modes and superfluidity of a two-dimensional ultracold Bose gas

  title={Collective modes and superfluidity of a two-dimensional ultracold Bose gas},
  author={Vijay Pal Singh and Ludwig Mathey},
  journal={arXiv: Quantum Gases},
The collective modes of a quantum liquid shape and impact its properties profoundly, including its emergent phenomena such as superfluidity. Here we present how a two-dimensional Bose gas responds to a moving lattice potential. In particular we discuss how the induced heating rate depends on the interaction strength and the temperature. This study is motivated by the recent measurements of Sobirey {\it et al.} arXiv:2005.07607 (2020), for which we provide a quantitative understanding. Going… 

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