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arXiv · 1103.2461

On the Integrability of the Rabi Model

Daniel Braak
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Abstract

The exact spectrum of the Rabi hamiltonian is analytically found for arbitrary coupling strength and detuning. I present a criterion for integrability of quantum systems containing discrete degrees of freedom which shows that in this case a finite symmetry group may entail integrability, even without the presence of conserved charges beyond the hamiltonian itself. Moreover, I introduce and solve a natural generalization of the Rabi model which has no symmetries and is therefore probably the smallest non-integrable physical system.

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Daniel Braak. 2011-12-20. On the Integrability of the Rabi Model. https://doi.org/10.1103/physrevlett.107.100401

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