International Conference on Strongly Correlated Electron Systems (SCES)

Quantum Instability in the Ultrastrong Coupling Regime of the Dicke Model

Hiroki Majima

Published Mar 18, 2020• 0 citations

Abstract

We study composite quantum systems, like the Dicke model (or the generalized quantum Rabi model), in the absence of external driving by resorting to methods from quantum field theory.It is shown that the usually neglected counter-rotating part of the Hamiltonian relates to the vacuum instability and generates an irreversible time evolution.To discuss the stability of the quantum dissipative system due to the influence of an Jaynes-Cummings Hamiltonian and the dissipative force (counter-rotating term) under situation, we derive a behavior for large time for a vacuum survival probability of the dissipative system.In the ultra-strong coupling regime, we show that the timedependent coherent state generated by an interaction Hamiltonian behaves non-unitary irreversible time evolution.

DOI: 10.7566/jpscp.30.011025

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