arXiv:2301.10488

Emergence of a Bose polaron in a small ring threaded by the Aharonov-Bohm flux

Fabian Brauneis, Areg Ghazaryan, H.‐W. Hammer, Artem G. Volosniev

Published Jan 25, 2023• 0 citations

Abstract

The model of a ring threaded by the Aharonov-Bohm flux underlies our understanding of a coupling between gauge potentials and matter. The typical formulation of the model is based upon a single particle picture, and should be extended when interactions with other particles become relevant. Here, we illustrate such an extension for a particle in an Aharonov-Bohm ring subject to interactions with a weakly interacting Bose gas. We show that the ground state of the system can be described using the Bose polaron concept -- a particle dressed by interactions with a bosonic environment. We connect the energy spectrum to the effective mass of the polaron, and demonstrate how to change currents in the system by tuning boson-particle interactions. Our results suggest the Aharonov-Bohm ring as a platform for studying coherence and few- to many-body crossover of quasi-particles that arise from an impurity immersed in a medium.

DOI: 10.48550/arxiv.2301.10488

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