Hidden quasi-local charges and Gibbs ensemble in a Lindblad system

TL;DR

This paper studies driven spin chains with hidden quasi-local charges, revealing multiple steady states and a Gibbs ensemble structure, by exactly computing non-equilibrium steady states using Matrix Product Operators.

Contribution

It introduces a family of Lindblad models with hidden symmetries and quasi-local charges, providing exact solutions and linking to quantum many body scars in open systems.

Findings

Multiple non-equilibrium steady states identified

Exact Matrix Product Operator representations derived

Emergence of Gibbs ensemble from hidden charges

Abstract

We consider spin-1/2 chains with external driving that breaks the continuous symmetries of the Hamiltonian. We introduce a family of models described by the Lindblad equation with local jump operators. The models have hidden strong symmetries in the form of quasi-local charges, leading to multiple non-equilibrium steady states. We compute them exactly in the form of Matrix Product Operators, and argue that they are the analogues of quantum many body scars in the Lindbladian setting. We observe that the dynamics leads to the emergence of a Gibbs ensemble constructed from the hidden charges.