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arXiv · 1810.10302

Variational approaches to quantum impurities: from the Fr\"{o}hlich polaron to the angulon

Xiang Li·Giacomo Bighin·Enderalp Yakaboylu·Mikhail Lemeshko
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Abstract

Problems involving quantum impurities, in which one or a few particles are interacting with a macroscopic environment, represent a pervasive paradigm, spanning across atomic, molecular, and condensed-matter physics. In this paper we introduce new variational approaches to quantum impurities and apply them to the Fr\"{o}hlich polaron -- a quasiparticle formed out of an electron (or other point-like impurity) in a polar medium, and to the angulon -- a quasiparticle formed out of a rotating molecule in a bosonic bath. We benchmark these approaches against established theories, evaluating their accuracy as a function of the impurity-bath coupling.

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Xiang Li, Giacomo Bighin, Enderalp Yakaboylu, Mikhail Lemeshko. 2018-10-24. Variational approaches to quantum impurities: from the Fr\"{o}hlich polaron to the angulon. https://doi.org/10.1080/00268976.2019.1567852

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