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arXiv · 2005.06485

Renormalisation group flow of the Jaynes-Cummings model

Anton Ilderton
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Abstract

The Jaynes-Cummings model is a cornerstone of light-matter interactions. While finite, the model provides an illustrative example of renormalisation in perturbation theory. We show, however, that exact renormalisation reveals a rich non-perturbative structure, and that the model provides a physical example of a theory with a chaotic coupling trajectory and multi-valued beta-function. We also construct an exact Wilsonian-like renormalisation group flow for the effective scattering matrix, and show how multi-valued features arise in the flow. Our results shed light on non-perturbative aspects of renormalisation and on the structure of the Jaynes-Cummings model itself.

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Anton Ilderton. 2020-05-13. Renormalisation group flow of the Jaynes-Cummings model. https://doi.org/10.1103/physrevlett.125.130402

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