Saved in:
Bibliographic Details
Main Authors: Chen, Yuetao, Chang, Shoukang, Gao, Shaoyan
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2404.15942
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917649060986880
author Chen, Yuetao
Chang, Shoukang
Gao, Shaoyan
author_facet Chen, Yuetao
Chang, Shoukang
Gao, Shaoyan
contents Parity-time (PT ) symmetric systems are gain-loss systems whose dynamics are governed by non-Hermitian Hamiltonians with degeneracies at exceptional-points (EPs) and has been studied in various photonic, electrical, mechanical systems, and so on. However, it is still an open question how to capture PT symmetry phase transition in electronic system where the transport properties of electron will be dramatically effected. Fortunately, the hybridization between photon and electron offers a novel way not only to control but also probe material properties. Here, we investigate a cavity coupled to a non-Hermitian Su-Schrieffer-Heeger (SSH) chain within mean-field ansatzs. We find that Squeezed Displaced Schrodinger cat (SDSc) will emerge with high fidelity in cavity ground state when PT -symmetry is broken and the fidelity will experience a sharp drop from almost 1 to 0 as PT symmetry recovers. Additionally, in semiclassical limit, we find that there exists local extrema at two sides of $x=0$ in semiclassical photon Hamiltonian $H_{\rm eff}(x, p)$, a clear signature of the emergence of SDSc state in cavity ground state. Thus, the appearance of SDSc state can be used to capture PT-symmetry phase transition which can not be modified by cavity mode. Besides, we exploit the cavity ground state to estimate the phase in the optical interferometer, and show that the quantum Fisher information and nonclassicality will sharply decline at EPs. This reveals that PT-symmetry breaking in electronic materials can also be captured by the quantum Fisher information and nonclassicality in phase estimation.
format Preprint
id arxiv_https___arxiv_org_abs_2404_15942
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Squeezed Displaced Schrödinger-cat state as a signature of the PT-symmetry phase transition
Chen, Yuetao
Chang, Shoukang
Gao, Shaoyan
Quantum Physics
Parity-time (PT ) symmetric systems are gain-loss systems whose dynamics are governed by non-Hermitian Hamiltonians with degeneracies at exceptional-points (EPs) and has been studied in various photonic, electrical, mechanical systems, and so on. However, it is still an open question how to capture PT symmetry phase transition in electronic system where the transport properties of electron will be dramatically effected. Fortunately, the hybridization between photon and electron offers a novel way not only to control but also probe material properties. Here, we investigate a cavity coupled to a non-Hermitian Su-Schrieffer-Heeger (SSH) chain within mean-field ansatzs. We find that Squeezed Displaced Schrodinger cat (SDSc) will emerge with high fidelity in cavity ground state when PT -symmetry is broken and the fidelity will experience a sharp drop from almost 1 to 0 as PT symmetry recovers. Additionally, in semiclassical limit, we find that there exists local extrema at two sides of $x=0$ in semiclassical photon Hamiltonian $H_{\rm eff}(x, p)$, a clear signature of the emergence of SDSc state in cavity ground state. Thus, the appearance of SDSc state can be used to capture PT-symmetry phase transition which can not be modified by cavity mode. Besides, we exploit the cavity ground state to estimate the phase in the optical interferometer, and show that the quantum Fisher information and nonclassicality will sharply decline at EPs. This reveals that PT-symmetry breaking in electronic materials can also be captured by the quantum Fisher information and nonclassicality in phase estimation.
title Squeezed Displaced Schrödinger-cat state as a signature of the PT-symmetry phase transition
topic Quantum Physics
url https://arxiv.org/abs/2404.15942