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arXiv · 1809.01204

Theory of the Rotating Polaron: Spectrum and Self-Localization

Enderalp Yakaboylu·Bikashkali Midya·Andreas Deuchert·Nikolai Leopold·Mikhail Lemeshko
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Abstract

We study a quantum impurity possessing both translational and internal rotational degrees of freedom interacting with a bosonic bath. Such a system corresponds to a `rotating polaron', which can be used to model, e.g., a rotating molecule immersed in an ultracold Bose gas or superfluid Helium. We derive the Hamiltonian of the rotating polaron and study its spectrum in the weak- and strong-coupling regimes using a combination of variational, diagrammatic, and mean-field approaches. We reveal how the coupling between linear and angular momenta affects stable quasiparticle states, and demonstrate that internal rotation leads to an enhanced self-localization in the translational degrees of freedom.

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Enderalp Yakaboylu, Bikashkali Midya, Andreas Deuchert, Nikolai Leopold, Mikhail Lemeshko. 2018-09-04. Theory of the Rotating Polaron: Spectrum and Self-Localization. https://doi.org/10.1103/physrevb.98.224506

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