Quantum Mpemba Effect in Dissipative Spin Chains at Criticality

TL;DR

This paper explores the quantum Mpemba effect in dissipative spin chains at criticality, showing that quantum phase transitions can enhance anomalous relaxation phenomena in open quantum systems.

Contribution

It demonstrates the emergence of a strong quantum Mpemba effect at critical points in quantum spin chains, linking criticality to accelerated relaxation in open quantum systems.

Findings

Criticality enhances non-monotonic relaxation times.

Quantum phase transitions facilitate the quantum Mpemba effect.

Liouvillian spectrum structure underpins the phenomenon.

Abstract

The Quantum Mpemba Effect (QME) is the quantum counterpart of the classical Mpemba effect--a counterintuitive phenomenon in which a system initially at a higher temperature relax to thermal eauilibrium faster than one at a lower temperature. In this work, we investigate the QME in one-dimensional quantum spin chains coupled to a Markovian environment. By analyzing the full relaxation dynamics governed by the Lindblad master equation, we reveal the emergence of a strong quantum Mpemba effect at quantum critical points. Our findings reveal that criticality enhances the non-monotonic dependence of relaxation times on the initial temperature, leading to anomalously accelerated equilibration. This phenomenon is directly linked to the structure of the Liouvillian spectrum at criticality and the associated overlaps with the initial states. These findings demonstrate that quantum phase transitions could provide a natural setting for realizing and enhancing non-equilibrium phenomena in open quantum systems.