Dynamical non-Hermitian systems: Fingerprints and pure dephasing induced protection effect

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Ma, Wanchen, Zhang, Hao, Liu, Junjie
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909680720150528
author Ma, Wanchen
Zhang, Hao
Liu, Junjie
author_facet Ma, Wanchen
Zhang, Hao
Liu, Junjie
contents Non-Hermitian systems have shown promising potential for realizing quantum information tasks that lack counterparts in the Hermitian realm. Understanding the dynamical characteristics of non-Hermitian systems as reflected in information-theoretic quantities is essential for advancing their applications. Here we investigate dynamics of trace distance and concurrence, which quantify information flow and entanglement, respectively, in non-Hermitian qubit systems exhibiting either parity-time or anti-parity-time symmetry. We identify dynamical fingerprints from the system density matrix which provide a unified explanation to the common oscillation and relaxation dynamics shared by trace distance and concurrence observed in existing studies. We further investigate the fate of dynamical fingerprints under the impact of pure dephasing. Surprisingly, we find that pure dephasing can slow down the inherent relaxation of information flow and entanglement in non-Hermitian systems with unbroken anti-parity-time symmetry, suggesting a passive environment-assisted information protection in this class of non-Hermitian systems. Our findings enhance our understanding of dynamical non-Hermitian systems and have specific relevance to their information-oriented applications.
format Preprint
id arxiv_https___arxiv_org_abs_2506_12298
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Dynamical non-Hermitian systems: Fingerprints and pure dephasing induced protection effect
Ma, Wanchen
Zhang, Hao
Liu, Junjie
Quantum Physics
Statistical Mechanics
Non-Hermitian systems have shown promising potential for realizing quantum information tasks that lack counterparts in the Hermitian realm. Understanding the dynamical characteristics of non-Hermitian systems as reflected in information-theoretic quantities is essential for advancing their applications. Here we investigate dynamics of trace distance and concurrence, which quantify information flow and entanglement, respectively, in non-Hermitian qubit systems exhibiting either parity-time or anti-parity-time symmetry. We identify dynamical fingerprints from the system density matrix which provide a unified explanation to the common oscillation and relaxation dynamics shared by trace distance and concurrence observed in existing studies. We further investigate the fate of dynamical fingerprints under the impact of pure dephasing. Surprisingly, we find that pure dephasing can slow down the inherent relaxation of information flow and entanglement in non-Hermitian systems with unbroken anti-parity-time symmetry, suggesting a passive environment-assisted information protection in this class of non-Hermitian systems. Our findings enhance our understanding of dynamical non-Hermitian systems and have specific relevance to their information-oriented applications.
title Dynamical non-Hermitian systems: Fingerprints and pure dephasing induced protection effect
topic Quantum Physics
Statistical Mechanics
url https://arxiv.org/abs/2506.12298