Exact dynamics of quantum dissipative $XX$ models: Wannier-Stark localization in the fragmented operator space

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Teretenkov, Alexander, Lychkovskiy, Oleg
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866911889262379008
author Teretenkov, Alexander
Lychkovskiy, Oleg
author_facet Teretenkov, Alexander
Lychkovskiy, Oleg
contents We address dissipative dynamics of the one-dimensional nearest-neighbour $XX$ spin-$1/2$ chain governed by the Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) equation. In the absence of dissipation the model is integrable. We identify a broad class of dissipative terms that generically destroy integrability but leave the operator space of the model fragmented into an extensive number of dynamically disjoint subspaces of varying dimensions. In sufficiently small subspaces the GKSL equation in the Heisenberg representation can be easily solved, sometimes in a closed analytical form. We provide an example of such an exact solution for a specific choice of dissipative terms. It is found that observables experience the Wannier-Stark localization in the corresponding operator subspace. As a result, the expectation values of the observables are linear combinations of essentially a few discrete decay modes, the long time dynamics being governed by the slowest mode. We examine the complex Liouvillian eigenvalue corresponding to this latter mode as a function of the dissipation strength. We find an exceptional point at a critical dissipation strength that separates oscillating and non-oscillating decay. We also describe a different type of dissipation that leads to a single decay mode in the whole operator subspace. Finally, we point out that our exact solutions of the GKSL equation entail exact solutions of the Schrödinger equation describing the quench dynamics in closed spin ladders dual to the dissipative spin chains.
format Preprint
id arxiv_https___arxiv_org_abs_2405_17310
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Exact dynamics of quantum dissipative $XX$ models: Wannier-Stark localization in the fragmented operator space
Teretenkov, Alexander
Lychkovskiy, Oleg
Strongly Correlated Electrons
Quantum Physics
We address dissipative dynamics of the one-dimensional nearest-neighbour $XX$ spin-$1/2$ chain governed by the Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) equation. In the absence of dissipation the model is integrable. We identify a broad class of dissipative terms that generically destroy integrability but leave the operator space of the model fragmented into an extensive number of dynamically disjoint subspaces of varying dimensions. In sufficiently small subspaces the GKSL equation in the Heisenberg representation can be easily solved, sometimes in a closed analytical form. We provide an example of such an exact solution for a specific choice of dissipative terms. It is found that observables experience the Wannier-Stark localization in the corresponding operator subspace. As a result, the expectation values of the observables are linear combinations of essentially a few discrete decay modes, the long time dynamics being governed by the slowest mode. We examine the complex Liouvillian eigenvalue corresponding to this latter mode as a function of the dissipation strength. We find an exceptional point at a critical dissipation strength that separates oscillating and non-oscillating decay. We also describe a different type of dissipation that leads to a single decay mode in the whole operator subspace. Finally, we point out that our exact solutions of the GKSL equation entail exact solutions of the Schrödinger equation describing the quench dynamics in closed spin ladders dual to the dissipative spin chains.
title Exact dynamics of quantum dissipative $XX$ models: Wannier-Stark localization in the fragmented operator space
topic Strongly Correlated Electrons
Quantum Physics
url https://arxiv.org/abs/2405.17310