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arXiv · 1308.2821

Effect of decoherence on the Berry phase of a spin-half in a rotating magnetic field

Xin Li·Yu Shi
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Abstract

We investigate the decoherence effect of a bosonic bath on the Berry phase of a spin-1/2 in a time-dependent magnetic field, without making the Markovian approximation. A two-cycle process resulting in a pure Berry phase is considered. The low-frequency quantum noise significantly affects the Berry phase. In the adiabatic limit, the high-frequency quantum noise only has a small effect. The result is also valid in some more general situations.

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Xin Li, Yu Shi. 2013-08-13. Effect of decoherence on the Berry phase of a spin-half in a rotating magnetic field. https://doi.org/10.1209/0295-5075%2F103%2F20005

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