Cavity Optomechanical Sensing and Manipulation of an Atomic Persistent Current*

One of the challenging tasks of atomic physics is to sense the circulation of a rotating annular Bose-Einstein condensate (BEC). Here, we propose a versatile technique¹ that overcomes this outstanding problem by utilizing tools of cavity optomechanics. The model under consideration is an annular rotating BEC interacting with orbital angular momentum carrying light beams inside an optical resonator. It is the first platform that can measure the rotation of a ring BEC with minimal destruction, in situ and in real-time, unlike the existing fully destructive techniques. For experimentally accessible parameters, the proposed method improves the rotation sensitivity of ring BECs by three orders of magnitude. The model also shows a unique way to manipulate rotating matter waves and generate optomechanical entanglement between persistent currents. Our work constitutes a novel paradigm for the sensing, characterization, and coherent manipulation of the atomic current. This opens up the possibility to use atomic superflow for useful applications such as storage and retrieval of information.

1. P. Kumar et.al., Phys. Rev. Lett. 127, 113601 (2021).