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arXiv · 1910.07338

Relaxation dynamics in double-spin systems

Philipp Stegmann·Jürgen König·Björn Sothmann
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Abstract

We consider the relaxation dynamics of two spins coupled to a common bosonic bath. The time evolution is simulated by a generalized master equation derived within a real-time diagrammatic approach. Interference effects due to the coherent coupling to the common bath give rise to characteristic features in the relaxation dynamics after a quench or during a periodic external driving. In particular, we find that the long-time behavior during periodic driving depends sensitively on the initial state as well as on system parameters such as coupling asymmetries. When coupled to more than a single reservoir, the interference effects can lead to a cooling mechanism for one of the bosonic reservoirs.

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Philipp Stegmann, Jürgen König, Björn Sothmann. 2019-10-16. Relaxation dynamics in double-spin systems. https://doi.org/10.1103/physrevb.101.075411

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