Transport and integrability-breaking in non-Hermitian many-body quantum systems

verfasst von

Dylan E. Mahoney, Jonas Richter

Abstract

Describing open quantum systems in terms of effective non-Hermitian Hamiltonians gives rise to nonunitary time evolution. In this paper we study the impact of nonunitary dynamics on the emergent hydrodynamics in quantum systems with a global conservation law. To this end we demonstrate how linear-response correlation functions can be generalized and interpreted in the case of non-Hermitian systems. Moreover we show that dynamical quantum typicality provides an efficient numerical approach to evaluate such correlation functions, even though the nonunitary dynamics leads to subtleties that are absent in the Hermitian case. As a point of reference for our analysis, we consider the Hermitian spin-1/2 XXZ chain, whose high-temperature transport properties have been characterized extensively in recent years. Here we explore the resulting hydrodynamics for different non-Hermitian perturbations of the XXZ chain. We also discuss the role of integrability by studying the complex energy-level statistics of the non-Hermitian quantum models.

Organisationseinheit(en)

Institut für Theoretische Physik

Externe Organisation(en)

Stanford University

Typ

Artikel

Journal

Physical Review B

Band

110

Anzahl der Seiten

13

ISSN

2469-9950

Publikationsdatum

04.10.2024

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Elektronische, optische und magnetische Materialien, Physik der kondensierten Materie

Elektronische Version(en)

https://doi.org/10.48550/arXiv.2403.01681 (Zugang: Offen)
https://doi.org/10.1103/PhysRevB.110.134302 (Zugang: Geschlossen)