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arXiv · 2410.18694

Quantifying the rotating-wave approximation of the Dicke model

Leonhard Richter·Daniel Burgarth·Davide Lonigro
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Abstract

We analytically find quantitative, non-perturbative bounds to the validity of the rotating-wave approximation (RWA) for the multi-atom generalization of the quantum Rabi model: the Dicke model. Precisely, we bound the norm of the difference between the evolutions of states generated by the Dicke model and its rotating-wave approximated counterpart, that is, the Tavis-Cummings model. The intricate role of the parameters of the model in determining the bounds is discussed and compared with numerical results. Our bounds are intrinsically state-dependent and, in particular, capture a nontrivial dependence on the total angular momentum of the initial state; this behaviour also seems to be confirmed by accompanying numerical results.

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Leonhard Richter, Daniel Burgarth, Davide Lonigro. 2024-10-24. Quantifying the rotating-wave approximation of the Dicke model. https://doi.org/10.1088/1751-8121%2Fae42a3

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