English
Related papers

Related papers: Optimal time for sensing in open quantum systems

200 papers

We formulate a quantum arrival time measurement process for a Bosonic many-particle system, with the aim of extracting statistical information on single-particle properties. The arrival time is based on a dynamical multi-particle absorption…

Quantum Physics · Physics 2025-05-28 Jukka Kiukas , Andreas Ruschhaupt

We study the problem of estimating the Schwarzschild radius of a massive body using Gaussian quantum probe states. Previous calculations assumed that the probe state remained pure after propagating a large distance. In a realistic scenario,…

Quantum Physics · Physics 2016-05-18 Sebastian P. Kish , Timothy C. Ralph

The Quantum Fisher Information matrix (QFIM) is a central metric in promising algorithms, such as Quantum Natural Gradient Descent and Variational Quantum Imaginary Time Evolution. Computing the full QFIM for a model with $d$ parameters,…

Quantum Physics · Physics 2021-10-20 Julien Gacon , Christa Zoufal , Giuseppe Carleo , Stefan Woerner

Various schemes have been proposed to overcome the drawback of the decoherence on quantum-enhanced parameter estimation. Here we suggest an alternative method, quantum feedback, to enhance the parameter precision of optimal quantum…

Quantum Physics · Physics 2015-06-24 Qiang Zheng , Li Ge , Yao Yao , Qi-jun Zhi

Quantum Fisher information (QFI) is an important feature for the precision of quantum parameter estimation based on the quantum Cram\'er-Rao inequality. When the quantum state satisfies the von Neumann-Landau equation, the local quantum…

Quantum Physics · Physics 2018-02-27 Shao-xiong Wu , Yang Zhang , Chang-shui Yu

Quantum-enhanced sensing is commonly benchmarked using the quantum Fisher information (QFI), often interpreted as a direct indicator of achievable precision. However, this quantity acquires operational meaning only within a fully specified…

Quantum Physics · Physics 2026-03-10 Zdeněk Hradil , Jaroslav Řeháček

We consider the impact that temporal correlations in the measurement statistics can have on the achievable precision in a sequential metrological protocol. In this setting, and for a single quantum probe, we establish that it is the…

Quantum Physics · Physics 2024-04-02 Eoin O'Connor , Steve Campbell , Gabriel T. Landi

We describe a compact and reliable method to calculate the Fisher information for the estimation of a dynamical parameter in a continuously measured linear Gaussian quantum system. Unlike previous methods in the literature, which involve…

Quantum Physics · Physics 2017-06-08 Marco G. Genoni

The quantum Fisher information (QFI) associated with a particular process applied to a many-body quantum system has been suggested as a diagnostic for the nature of the system's quantum state, e.g., a thermal density matrix vs. a pure state…

Statistical Mechanics · Physics 2023-04-05 Fernando Iniguez , Mark Srednicki

In this work, we propose new methods of parameter estimation using stochastic sampling quantum phase-space simulations. We show that it is possible to compute the quantum Fisher information (QFI) from semiclassical stochastic samples using…

Quantum Physics · Physics 2026-04-01 Thakur G. M. Hiranandani , Joseph J. Hope , Simon A. Haine

Quantum metrology studies the ultimate limit of precision in estimating a physical quantity if quantum strategies are exploited. Here we investigate the evolution of a two-level atom as a detector which interacts with a massless scalar…

General Relativity and Quantum Cosmology · Physics 2015-01-28 Zehua Tian , Jieci Wang , Heng Fan , Jiliang Jing

By employing the Naimark dilation, we establish a fundamental connection between non-Hermitian quantum sensing and post-selected measurements. The sensitivity of non-Hermitian quantum sensors is determined by the effective quantum Fisher…

Quantum Physics · Physics 2025-05-13 Neng Zeng , Tao Liu , Keyu Xia , Yu-Ran Zhang , Franco Nori

Resolving frequencies in a time-dependent field is classically limited by the measurement bandwidth. Using tools from quantum metrology and quantum control may overcome this limit, yet the full advantage afforded by entanglement so far…

Quantum Physics · Physics 2025-09-03 Anirban Dey , Sara Mouradian , Cosmo Lupo , Zixin Huang

We calculate the quantum Fisher information for a generic many-body fermionic system in a pure state depending on a parameter. We discuss the situations where the parameter is imprinted in the basis states, in the state coefficients, or…

Quantum Physics · Physics 2023-03-21 Olivier Giraud , Mark-Oliver Goerbig , Daniel Braun

Multipartite entanglement, such as witnessed through the quantum Fisher information (QFI), is a crucial resource for quantum technologies, but its experimental certification is highly challenging. Here, we propose an experimentally friendly…

Quantum Physics · Physics 2021-09-01 Ricardo Costa de Almeida , Philipp Hauke

In this work, we present a lower bound on the quantum Fisher information (QFI) which is efficiently computable on near-term quantum devices. This bound itself is of interest, as we show that it satisfies the canonical criteria of a QFI…

Quantum Physics · Physics 2021-12-03 Akira Sone , M. Cerezo , Jacob L. Beckey , Patrick J. Coles

The Quantum Fisher Information (QFI) is a geometric measure of state deformation calculated along the trajectory parameterizing an ensemble of quantum states. It serves as a key concept in quantum metrology, where it is linked to the…

Quantum Physics · Physics 2025-12-05 Gabriela Wójtowicz , Susana F. Huelga , Marek M. Rams , Martin B. Plenio

Quantum Fisher information (QFI) is a central concept in quantum sciences used to quantify the ultimate precision limit of parameter estimation, detect quantum phase transitions, witness genuine multipartite entanglement, or probe…

Quantum Physics · Physics 2026-02-09 Carlos L. Benavides-Riveros , Tomasz Wasak , Alessio Recati

Symmetry breaking underlies diverse phenomena from phase transitions in condensed matter to fundamental interactions in gauge theories. Despite many proposed indicators, a general quantification of symmetry breaking that is faithful,…

Statistical Mechanics · Physics 2025-09-10 Shion Yamashika , Shimpei Endo , Hiroyasu Tajima

In an open quantum system, we study the evolution of a two-level atom as a detector which interacts with given environments. For a uniformly accelerated two-level atom coupled to a massless scalar field in the Minkowski vacuum, when it…

Quantum Physics · Physics 2020-07-28 Zixu Zhao , Qiyuan Pan , Jiliang Jing