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arXiv · 1709.00591

Effective Formalism for Open Quantum System Dynamics: Time-coarse-graining Approach

Chang-Woo Lee·Changsuk Noh·Jaewan Kim
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Abstract

We formulate an effective-description framework for the dynamics of open quantum systems by extending the time-coarse-graining formalism to open systems. Our coarse-graining procedure efficiently removes high-frequency processes which are responsible for coherences between lower- and upper-manifold states and are irrelevant when considering only low-energy dynamics. We investigate the regime of validity of the resulting coarse-grained master equation by applying it to multi-level atoms driven by far-detuned lasers. Except for such high-frequency coherences, we find good agreement between the exact and coarse-grained dynamics unless the driving lasers are too strong or the initial high-frequency coherences are sizable.

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Chang-Woo Lee, Changsuk Noh, Jaewan Kim. 2017-09-02. Effective Formalism for Open Quantum System Dynamics: Time-coarse-graining Approach. https://doi.org/10.1103/physreva.97.012102

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