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arXiv · 1805.03422

Long-range interactions and symmetry-breaking in quantum gases through optical feedback

Yong-Chang Zhang·Valentin Walther·Thomas Pohl
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Abstract

We consider a quasi two-dimensional atomic Bose Einstein condensate interacting with a near-resonant laser field that is back-reflected onto the condensate by a planar mirror. We show that this single-mirror optical feedback leads to an unusual type of effective interaction between the ultracold atoms giving rise to a rich spectrum of ground states. In particular, we find that it can cause the spontaneous contraction of the quasi two-dimensional condensate to form a self-bound one-dimensional chain of mesoscopic quantum droplets, and demonstrate that the observation of this exotic effect is within reach of current experiments.

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Yong-Chang Zhang, Valentin Walther, Thomas Pohl. 2018-05-09. Long-range interactions and symmetry-breaking in quantum gases through optical feedback. https://doi.org/10.1103/physrevlett.121.073604

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