Hermitian vs non-Hermitian quantum thermometry

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Hminat, Anass, Slaoui, Abdallah, Laamara, Rachid Ahl, Telmini, Mourad
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915493607112704
author Hminat, Anass
Slaoui, Abdallah
Laamara, Rachid Ahl
Telmini, Mourad
author_facet Hminat, Anass
Slaoui, Abdallah
Laamara, Rachid Ahl
Telmini, Mourad
contents We investigate the dephasing dynamics of a qubit as an effective mechanism for estimating the temperature of its surrounding environment for different symmetrizes. Our approach is fundamentally quantum, leveraging the qubit's susceptibility to decoherence without necessitating thermal equilibrium with the system under study. We also examine how symmetry properties affect the accuracy of information retrieval and the robustness of quantum information storage in such systems, highlighting their potential advantages in mitigating decoherence effects. The optimization of quantum Fisher information is performed with respect to both the interaction duration and the environmental temperature, focusing on Ohmic-like spectral density environments. Furthermore, we explicitly identify the optimal qubit measurement that attains the quantum Cramer-Rao bound for precision. Our findings reveal that optimal estimation arises from a complex interplay between the qubit's dephasing dynamics and the Ohmic characteristics of the environment with a particular focus on non-Hermitian systems that exhibit enhanced resilience to decoherence. Notably, optimal estimation does not occur when the qubit reaches a stationary state nor under conditions of complete dephasing.
format Preprint
id arxiv_https___arxiv_org_abs_2509_10840
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Hermitian vs non-Hermitian quantum thermometry
Hminat, Anass
Slaoui, Abdallah
Laamara, Rachid Ahl
Telmini, Mourad
Quantum Physics
Mathematical Physics
We investigate the dephasing dynamics of a qubit as an effective mechanism for estimating the temperature of its surrounding environment for different symmetrizes. Our approach is fundamentally quantum, leveraging the qubit's susceptibility to decoherence without necessitating thermal equilibrium with the system under study. We also examine how symmetry properties affect the accuracy of information retrieval and the robustness of quantum information storage in such systems, highlighting their potential advantages in mitigating decoherence effects. The optimization of quantum Fisher information is performed with respect to both the interaction duration and the environmental temperature, focusing on Ohmic-like spectral density environments. Furthermore, we explicitly identify the optimal qubit measurement that attains the quantum Cramer-Rao bound for precision. Our findings reveal that optimal estimation arises from a complex interplay between the qubit's dephasing dynamics and the Ohmic characteristics of the environment with a particular focus on non-Hermitian systems that exhibit enhanced resilience to decoherence. Notably, optimal estimation does not occur when the qubit reaches a stationary state nor under conditions of complete dephasing.
title Hermitian vs non-Hermitian quantum thermometry
topic Quantum Physics
Mathematical Physics
url https://arxiv.org/abs/2509.10840