Toggle Main Menu Toggle Search

Open Access padlockePrints

Critical Quantum Metrology with Fully-Connected Models: From Heisenberg to Kibble-Zurek Scaling

Lookup NU author(s): Dr Obinna AbahORCiD



This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


Phase transitions represent a compelling tool for classical and quantum sensing applications. It has been demonstrated that quantum sensors can in principle saturate the Heisenberg scaling, the ultimate precision bound allowed by quantum mechanics, in the limit of large probe number and long measurement time. Due to the critical slowing down, the protocol duration time is of utmost relevance in critical quantum metrology. However, how the long-time limit is reached remains in general an open question. So far, only two dichotomic approaches have been considered, based on either static or dynamical properties of critical quantum systems. Here, we provide a comprehensive analysis of the scaling of the quantum Fisher information for different families of protocols that create a continuous connection between static and dynamical approaches. In particular, we consider fully-connected models, a broad class of quantum critical systems of high experimental relevance. Our analysis unveils the existence of universal precision-scaling regimes. These regimes remain valid even for finite-time protocols and finite-size systems. We also frame these results in a general theoretical perspective, by deriving a precision bound for arbitrary time-dependent quadratic Hamiltonians.

Publication metadata

Author(s): Garbe L, Abah O, Felicetti S, Puebla R

Publication type: Article

Publication status: Published

Journal: Quantum Science and Technology

Year: 2022

Volume: 7

Issue: 3

Online publication date: 19/05/2022

Acceptance date: 04/05/2022

Date deposited: 30/05/2022

ISSN (electronic): 2058-9565

Publisher: Institute of Physics Publishing Ltd.


DOI: 10.1088/2058-9565/ac6ca5


Altmetrics provided by Altmetric