Dephasing-induced growth of discrete crystalline order in spin networks

TL;DR

This paper explores how dephasing influences the emergence and stabilization of discrete-time crystals in spin networks, revealing that environmental effects can promote crystalline order in non-equilibrium quantum systems.

Contribution

It demonstrates that dephasing can induce and stabilize discrete-time crystal phases in open quantum systems, a novel insight into dissipative quantum phase formation.

Findings

Dephasing promotes the growth of discrete crystalline order.

System evolves towards a DTC phase under environmental influence.

DTC stability can be achieved through dissipation effects.

Abstract

A quantum phase of matter can be understood from the symmetry of the system's Hamiltonian. The system symmetry along the time axis has been proposed to show a new phase of matter referred as discrete-time crystals (DTCs). A DTC is a quantum phase of matter in non-equilibrium systems, and it is also intimately related to the symmetry of the initial state. DTCs that are stable in isolated systems are not necessarily resilient to the influence from the external reservoir. In this paper, we discuss the dynamics of the DTCs under the influence of an environment. Specifically, we consider a non-trivial situation in which the initial state is prepared to partly preserve the symmetry of the Liouvillian. Our analysis shows that the entire system evolves towards a DTC phase and is stabilised by the effect of dephasing. Our results provide a new understanding of quantum phases emerging from the competition between the coherent and incoherent dynamics in dissipative non-equilibrium quantum systems.