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arXiv · 2006.02358

Open quantum systems decay across time

Juliane Klatt·Chahan Michael Kropf·Stefan Yoshi Buhmann
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Abstract

The description of an open quantum system's decay almost always requires several approximations as to remain tractable. Here, we first revisit the meaning, domain and seeming contradictions of a few of the most widely used of such approximations: semi-group Markovianity, linear response theory, Wigner--Weisskopf and rotating-wave approximation. Secondly, we derive an effective time-dependent decay theory and corresponding generalized quantum regression relations for an open quantum system linearly coupled to an environment. This theory covers all timescales, and subsumes the Markovian and linear-response results as limiting cases. Finally, we apply our theory to the phenomenon of quantum friction.

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Juliane Klatt, Chahan Michael Kropf, Stefan Yoshi Buhmann. 2020-06-03. Open quantum systems decay across time. https://doi.org/10.1103/physrevlett.126.210401

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