English
Related papers

Related papers: Cram\'er-Rao bound and quantum parameter estimatio…

200 papers

Critical properties of a quantum system are recognized as valuable resources for quantum metrology. In this work, we investigate the criticality-enhanced sensing in a quantum Rabi triangle system, which exhibits multiple phases. Around the…

Quantum Physics · Physics 2025-11-04 Yuyang Tang , Yu Yang , Min An , Fuli Li

Quantum Fisher information matrix (QFIM) is a core concept in theoretical quantum metrology due to the significant importance of quantum Cram\'{e}r-Rao bound in quantum parameter estimation. However, studies in recent years have revealed…

Quantum Physics · Physics 2020-03-27 Jing Liu , Haidong Yuan , Xiao-Ming Lu , Xiaoguang Wang

We formulate multiparameter quantum estimation in the parametric and semiparametric setting. While the Holevo Cram\'er-Rao bound (CRB) requires no substantial modifications in moving from the former to the latter, we generalize the Helstrom…

Quantum Physics · Physics 2020-08-10 Francesco Albarelli , Mankei Tsang , Animesh Datta

Quantifying measurement precision in quantum systems is vital for advancing quantum technologies such as sensing, communication, and computation. The quantum Fisher information (QFI) sets the ultimate precision bound in Hermitian systems;…

Quantum Physics · Physics 2026-03-12 Javid Naikoo , Ravindra W. Chhajlany , Jan Kołodyński , Adam Miranowicz

How precisely can we estimate cosmological parameters by performing a quantum measurement on a cosmological quantum state? In quantum estimation theory the variance of an unbiased parameter estimator is bounded from below by the inverse of…

General Relativity and Quantum Cosmology · Physics 2017-10-17 Marcello Rotondo , Yasusada Nambu

Critical metrology relies on the precise preparation of a system in its ground state near a quantum phase transition point where quantum correlations get very strong. Typically this increases the quantum Fisher information with respect to…

Quantum Physics · Physics 2024-02-12 Christoph Hotter , Helmut Ritsch , Karol Gietka

We revisit the problem of computing submatrices of the Cram\'er-Rao bound (CRB), which lower bounds the variance of any unbiased estimator of a vector parameter $\vth$. We explore iterative methods that avoid direct inversion of the Fisher…

Information Theory · Computer Science 2015-06-04 Paul Tune

The unavoidable interaction between a quantum system and the external noisy environment can be mimicked by a sequence of stochastic measurements whose outcomes are neglected. Here we investigate how this stochasticity is reflected in the…

Quantum Physics · Physics 2018-03-30 Matthias M. Müller , Stefano Gherardini , Augusto Smerzi , Filippo Caruso

Quantum information science currently poses a troubling contradiction. It can be summarized as: (1) To factor efficiently, quantum computers must perform exponentially precise energy estimation. (2) Exponentially precise energy estimation…

General Physics · Physics 2025-03-17 Liam P. McGuinness

We derive lower bounds on the variance of estimators in quantum metrology by choosing test observables that define constraints on the unbiasedness of the estimator. The quantum bounds are obtained by analytical optimization over all…

Quantum Physics · Physics 2023-07-27 M. Gessner , A. Smerzi

Quantum parameter estimation with Hermitian systems has been applied in various fields, but there are relatively few results concerning non-Hermitian systems. Here, we study the quantum parameter estimation for general non-Hermitian…

Quantum Physics · Physics 2023-09-06 Xinglei Yu , Chengjie Zhang

The minimum error of unbiased parameter estimation is quantified by the quantum Fisher information in accordance to the Cram\'{e}r-Rao bound. We indicate that only superposed NOON states by simultaneous measurements can achieve the maximum…

Quantum Physics · Physics 2015-05-28 Y. R. Zhang , G. R. Jin , J. P. Cao , W. M. Liu , H. Fan

Quantum Fisher Information (QFI) is a fundamental quantity in quantum parameter estimation theory, characterizing the ultimate precision bound of parameter estimation. In this work, we investigate QFI for quantum states in non-Hermitian…

Quantum Physics · Physics 2025-05-27 L. H. Wei , H. J. Xing , L. B. Fu , H. D. Liu

Quantum estimation theory provides optimal observations for various estimation problems for unknown parameters in the state of the system under investigation. However, the theory has been developed under the assumption that every observable…

Quantum Physics · Physics 2009-11-10 M. Hotta , M. Ozawa

Estimation of multiple parameters in an unknown Hamiltonian is investigated. We present upper and lower bounds on the time required to complete the estimation within a prescribed tolerance $\delta$. The lower bound is given on the basis of…

Quantum Physics · Physics 2018-01-10 Naoto Kura , Masahito Ueda

We develop a hybrid framework for quantum parameter estimation in the presence of nuisance parameters. In this Bayes-point scheme, the parameters of interest are treated as fixed non-random parameters while nuisance parameters are…

Quantum Physics · Physics 2025-10-21 Jianchao Zhang , Jun Suzuki

In this paper, we analyze the impact of compressed sensing with complex random matrices on Fisher information and the Cram\'{e}r-Rao Bound (CRB) for estimating unknown parameters in the mean value function of a complex multivariate normal…

Statistics Theory · Mathematics 2023-07-19 Pooria Pakrooh , Ali Pezeshki , Louis L. Scharf , Douglas Cochran , Stephen D. Howard

The Cramer-Rao product of the Fisher information and the variance of a probability density \rho(x), defined on a domain \Delta \in R^D, is found to have a minimum value reached by the density associated with the ground state of the harmonic…

Mathematical Physics · Physics 2010-01-20 J. S. Dehesa , A. R. Plastino , P. Sanchez-Moreno , C. Vignat

The attainability of the quantum Cram\'er-Rao bound [QCR], the ultimate limit in the precision of the estimation of a physical parameter, requires the saturation of the quantum information bound [QIB]. This occurs when the Fisher…

Quantum Physics · Physics 2017-04-26 Fabricio Toscano , Wellison P. Bastos , Ruynet L. de Matos Filho

This paper deals with Cram\'er-Rao inequalities in the context of nonextensive statistics and in estimation theory. It gives characterizations of generalized q-Gaussian distributions, and introduces generalized versions of Fisher…

Mathematical Physics · Physics 2012-06-05 J. -F. Bercher