Phases of the electronic two-level model under the rotating wave approximation

M. T. Thomaz; A. C. Aguiar Pinto; M. Moutinho

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arXiv · 1004.4008

Phases of the electronic two-level model under the rotating wave approximation

M. T. Thomaz·A. C. Aguiar Pinto·M. Moutinho

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Abstract

We present the time evolution of the electronic two-level model in the rotating wave approximation (RWA). We calculate the Aharonov-Anandan phase of the vector states with cyclic evolution either within the period of an external monochromatic electric field or the period corresponding to Rabi's frequency. The Aharonov-Anandan phase is shown to be dependent on the initial vector state, unless the system evolves in the adiabatic regime; in the latter case, the Aharonov-Anandan phase recovers Berry's phase. Our results are also discussed in the quasi-resonant regime.

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M. T. Thomaz, A. C. Aguiar Pinto, M. Moutinho. 2010-04-22. Phases of the electronic two-level model under the rotating wave approximation. https://arxiv.org/abs/1004.4008

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