Dynamical signatures of the Yang-Lee edge singularity in non-Hermitian systems

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Lu, Ming-Chu, Shi, Shun-Hui, Sun, Gaoyong
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866929725483515904
author Lu, Ming-Chu
Shi, Shun-Hui
Sun, Gaoyong
author_facet Lu, Ming-Chu
Shi, Shun-Hui
Sun, Gaoyong
contents The Yang-Lee edge singularity is an intriguing critical phenomenon characterized by nonunitary field theory. However, its experimental realization for interacting many-body systems remains elusive. We show that Yang-Lee edge singularities, regarded as many-body exceptional points, can be observed using both the self-normal and the associated-biorthogonal Loschmidt echoes, leveraging the advantages of nonunitary dynamics in non-Hermitian systems. The Loschmidt echoes are demonstrated to display unitary dynamics in the $\mathcal{PT}$-symmetric regime but exhibit nonunitary dynamics in the $\mathcal{PT}$ symmetry-broken regime, leading to a sharp change near an exceptional point. We hereby identify exceptional points in both the non-Hermitian transverse field Ising model and the Yang-Lee model, and determine the critical exponent that is consistent with nonunitary conformal field theory. This work provides a direct observation of Yang-Lee edge singularities in non-Hermitian many-body systems arising from nonunitary dynamics.
format Preprint
id arxiv_https___arxiv_org_abs_2407_20106
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Dynamical signatures of the Yang-Lee edge singularity in non-Hermitian systems
Lu, Ming-Chu
Shi, Shun-Hui
Sun, Gaoyong
Quantum Gases
The Yang-Lee edge singularity is an intriguing critical phenomenon characterized by nonunitary field theory. However, its experimental realization for interacting many-body systems remains elusive. We show that Yang-Lee edge singularities, regarded as many-body exceptional points, can be observed using both the self-normal and the associated-biorthogonal Loschmidt echoes, leveraging the advantages of nonunitary dynamics in non-Hermitian systems. The Loschmidt echoes are demonstrated to display unitary dynamics in the $\mathcal{PT}$-symmetric regime but exhibit nonunitary dynamics in the $\mathcal{PT}$ symmetry-broken regime, leading to a sharp change near an exceptional point. We hereby identify exceptional points in both the non-Hermitian transverse field Ising model and the Yang-Lee model, and determine the critical exponent that is consistent with nonunitary conformal field theory. This work provides a direct observation of Yang-Lee edge singularities in non-Hermitian many-body systems arising from nonunitary dynamics.
title Dynamical signatures of the Yang-Lee edge singularity in non-Hermitian systems
topic Quantum Gases
url https://arxiv.org/abs/2407.20106