Nonreciprocal and Long-Range Three-Body Interactions in Bose-Einstein Condensates Induced by Optical Feedback

We propose generating atom-atom three-body interactions in quantum gases by placing a quasi-two-dimensional Bose-Einstein condensate in front of two reflecting mirrors and illuminating it with dichromatic laser beams. These pumping fields traverse the condensate twice, thereby inducing a feedback effect on the atoms. We demonstrate that this optical feedback gives rise to an effective three-body interaction with unique long-range and nonreciprocal properties. Because of its long-range nature, this three-body interaction can give rise to various stable stationary droplet cluster states, as well as a distinct ring state that emerges through a purely self-organizing process. Furthermore, we show that the nonreciprocal nature of this interaction can lead to remarkable self-acceleration of the condensate. Additionally, our scheme offers a highly controllable setting, where pairwise two-body interactions can be tuned to vanish. This flexibility provides a promising route for exploring exotic physics associated with multibody interactions.