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arXiv · 2203.03302

Lindblad master equations for quantum systems coupled to dissipative bosonic modes

Simon B. Jäger·Tom Schmit·Giovanna Morigi·Murray J. Holland·Ralf Betzholz
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Abstract

We present a general approach to derive Lindblad master equations for a subsystem whose dynamics is coupled to dissipative bosonic modes. The derivation relies on a Schrieffer-Wolff transformation which allows to eliminate the bosonic degrees of freedom after self-consistently determining their state as a function of the coupled quantum system. We apply this formalism to the dissipative Dicke model and derive a Lindblad master equation for the atomic spins, which includes the coherent and dissipative interactions mediated by the bosonic mode. This master equation accurately predicts the Dicke phase transition and gives the correct steady state. In addition, we compare the dynamics using exact diagonalization and numerical integration of the master equation with the predictions of semiclassical trajectories. We finally test the performance of our formalism by studying the relaxation of a NOON state and show that the dynamics captures quantum metastability beyond the mean-field approximation.

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Simon B. Jäger, Tom Schmit, Giovanna Morigi, Murray J. Holland, Ralf Betzholz. 2022-03-07. Lindblad master equations for quantum systems coupled to dissipative bosonic modes. https://doi.org/10.1103/physrevlett.129.063601

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