Related papers: Signatures of Liouvillian exceptional points in a quantum thermal machine

Signatures of Liouvillian exceptional points in a quantum thermal machine

URL: http://arxiv.org/abs/2101.11553v3
Date: Mon, 22 Nov 2021 18:34:39 GMT
Title: Signatures of Liouvillian exceptional points in a quantum thermal machine
Authors: Shishir Khandelwal, Nicolas Brunner, G\'eraldine Haack
Abstract summary: We characterize a quantum thermal machine as a non-Hermitian quantum system. We show that the thermal machine features a number of Liouvillian exceptional points (EPs) for experimentally realistic parameters.
Score: 20.83362404425491
License: http://creativecommons.org/licenses/by-nc-nd/4.0/
Abstract: Viewing a quantum thermal machine as a non-Hermitian quantum system, we characterize in full generality its analytical time-dependent dynamics by deriving the spectrum of its non-Hermitian Liouvillian for an arbitrary initial state. We show that the thermal machine features a number of Liouvillian exceptional points (EPs) for experimentally realistic parameters, in particular a third-dorder exceptional point that leaves signatures both in short and long-time regimes. Remarkably, we demonstrate that this EP corresponds to a regime of critical decay for the quantum thermal machine towards its steady state, bearing a striking resemblance with a critically damped harmonic oscillator. These results open up exciting possibilities for the precise dynamical control of quantum thermal machines exploiting exceptional points from non-Hermitian physics and are amenable to state-of-the-art solid-state platforms such as semiconducting and superconducting devices.

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