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arXiv · 2012.06994

Approximating the two-mode two-photon Rabi model

David H. Wu·Victor V. Albert
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Abstract

The Rabi model describes the simplest nontrivial interaction between a few-level system and a bosonic mode, featuring in multiple seemingly unrelated systems of importance to quantum science and technology. While exact expressions for the energies of this model and its few-mode extensions have been obtained, they involve roots of transcendental functions and are thus cumbersome and unintuitive. Utilizing the symmetric generalized rotating wave approximation (S-GRWA), we develop a family of approximations to the energies of the two-mode two-photon Rabi model. The simplest elements of the family are analytically tractable, providing good approximations in regimes of interest such as ultra- and deep-strong coupling. Higher-order approximate energies can be used if more accuracy is required.

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BibTeXRIS

David H. Wu, Victor V. Albert. 2020-12-13. Approximating the two-mode two-photon Rabi model. https://doi.org/10.1016/j.physleta.2021.127779

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