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arXiv · 1502.02356

Does the Berry phase in a quantum optical system originate from the rotating wave approximation

Minghao Wang·L. F. Wei·J. Q. Liang
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Abstract

The Berry phase (BP) in a quantized light field demonstrated more than a decade ago (Phys. Rev. Lett. 89, 220404) has attracted considerable attentions, since it plays an important role in the cavity quantum electrodynamics. However, it is argued in a recent paper ( Phys. Rev. Lett. 108, 033601) that such a BP is just due to the rotating wave approximation (RWA) and the relevant BP should vanish beyond this approximation. Based on a consistent analysis we conclude in this letter that the BP in a generic Rabi model actually exists, no matter whether the RWA is applied. The existence of BP is also generalized to a three-level atom in the quantized cavity field.

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Minghao Wang, L. F. Wei, J. Q. Liang. 2015-02-13. Does the Berry phase in a quantum optical system originate from the rotating wave approximation. https://doi.org/10.1016/j.physleta.2015.02.006

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