Accelerating the approach of dissipative quantum spin systems towards stationarity through global spin rotations

Abstract

We consider open quantum systems whose dynamics is governed by a time-independent Markovian Lindblad Master equation. Such systems approach their stationary state on a timescale that is determined by the spectral gap of the generator of the Master equation dynamics. In the recent paper [Carollo et al., Phys. Rev. Lett. 127, 060401 (2021)] it was shown that under certain circumstances it is possible to exponentially accelerate the approach to stationarity by performing a unitary transformation of the initial state. This phenomenon can be regarded as the quantum version of the so-called Mpemba effect. The transformation of the initial state removes its overlap with the dynamical mode of the open system dynamics that possesses the slowest decay rate and thus determines the spectral gap. While this transformation can be exactly constructed in some cases, it is in practice challenging to implement. Here we show that even far simpler transformations constructed by a global unitary spin rotation allow to exponentially speed up relaxation. We demonstrate this using simple dissipative quantum spin systems, which are relevant for current quantum simulation and computation platforms based on trapped atoms and ions.

7 pages, 4 figures

References in corpus (8)

• Many-Body Physics with Individually-Controlled Rydberg Atoms
• Dissipative Phase Transition in Central Spin Systems
• Exponentially faster cooling in a colloidal system
• Critical dynamical properties of a first-order dissipative phase transition
• Universal non-equilibrium properties of dissipative Rydberg gases
• Exponentially accelerated approach to stationarity in Markovian open quantum systems through the Mpemba effect
• Driven-dissipative Ising Model: An exact field-theoretical analysis
• Phase diagram of quantum generalized Potts-Hopfield neural networks