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Decoherence-induced geometric phase in a multilevel atomic system

Shubhrangshu Dasgupta·Daniel A. Lidar
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Abstract

We consider the STIRAP process in a three-level atom. Viewed as a closed system, no geometric phase is acquired. But in the presence of spontaneous emission and/or collisional relaxation we show numerically that a non-vanishing, purely real, geometric phase is acquired during STIRAP, whose magnitude grows with the decay rates. Rather than viewing this decoherence-induced geometric phase as a nuisance, it can be considered an example of "beneficial decoherence": the environment provides a mechanism for the generation of geometric phases which would otherwise require an extra experimental control knob.

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Shubhrangshu Dasgupta, Daniel A. Lidar. 2006-12-24. Decoherence-induced geometric phase in a multilevel atomic system. https://doi.org/10.1088/0953-4075/40/9/s07

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