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Related papers: Quantum Fisher Information with Coherence

200 papers

We introduce a new kind of quantum measurement that is defined to be symmetric in the sense of uniform Fisher information across a set of parameters that injectively represent pure quantum states in the neighborhood of a fiducial pure…

Quantum Physics · Physics 2016-05-11 Nan Li , Christopher Ferrie , Jonathan A. Gross , Amir Kalev , Carlton M. Caves

We establish a quantum Fisher information (QFI) duality for distributed quantum sensor networks with local phase encoding. For any $N$-qubit probe state, where $N$ denotes the number of sensors, $F_Q(\boldsymbol{w}^\top \boldsymbol{\theta})…

Quantum Physics · Physics 2026-05-21 Farhad Farokhi

Informationally complete measurements form the foundation of universal quantum state reconstruction, while quantum parameter estimation is based on the local structure of the manifold of quantum states. Here we establish a general link…

Quantum Physics · Physics 2025-12-18 Rakesh Saini , Jukka Kiukas , Daniel Burgarth , Alexei Gilchrist

We discuss the advantages of using the approximate quantum Fourier transform (AQFT) in algorithms which involve periodicity estimations. We analyse quantum networks performing AQFT in the presence of decoherence and show that extensive…

Quantum Physics · Physics 2009-10-30 Adriano Barenco , Artur Ekert , Kalle-Antti Suominen , Päivi Törmä

We propose a universal language to assess macroscopic quantumness in terms of coherence, with a set of conditions that should be satisfied by any measure of macroscopic coherence. We link the framework to the resource theory of asymmetry.…

Quantum Physics · Physics 2016-03-01 Benjamin Yadin , Vlatko Vedral

We study the role of quantum entanglement (particle entanglement and mode entanglement) in optical phase estimation by employing the first and second quantization formalisms of quantum mechanics. The quantum Fisher information (QFI) is…

Quantum Physics · Physics 2016-09-23 Jaspreet Sahota , Nicolás Quesada , Daniel F. V. James

Variance and Fisher information are ingredients of the Cramer-Rao inequality. We regard Fisher information as a Riemannian metric on a quantum statistical manifold and choose monotonicity under coarse graining as the fundamental property of…

Quantum Physics · Physics 2009-11-07 Denes Petz

Recent theoretical and experimental work has shown that the quantum Fisher information associated with estimating the separation between two optical point sources remains finite at small separations, effectively opening new routes to…

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

As a method to extract information from optical system, imaging can be viewed as a parameter estimation problem. The fundamental precision in locating one emitter or estimating the separation between two incoherent emitters is bounded below…

Quantum Physics · Physics 2021-07-29 Ben Wang , Liang Xu , Lijian Zhang

To optimize the entanglement detection, we formulate the metrologically operational entanglement condition in quantum Fisher information by maximizing the QFI on the measurement orbit. Specifically, we consider two classes of typical local…

Quantum Physics · Physics 2024-10-28 Ao-Xiang Liu , Ma-Cheng Yang , Cong-Feng Qiao

Circular dichroism (CD) is a widely used technique for investigating optically chiral molecules, especially for biomolecules. It is thus of great importance that these parameters be estimated precisely so that the molecules with desired…

Quantum Physics · Physics 2021-12-28 Jiaxuan Wang , Girish S. Agarwal

We address the use of simple quantum probes for the spectral characterization of classical noisy environments. In our scheme a qubit interacts with a classical stochastic field describing environmental noise and is then measured after a…

Quantum Physics · Physics 2014-03-21 Claudia Benedetti , Fabrizio Buscemi , Paolo Bordone , Matteo G. A. Paris

We consider the general problem of estimating an unknown control parameter of an open quantum system. We establish a direct relation between the evolution of both system and environment and the precision with which the parameter can be…

Quantum Physics · Physics 2016-02-10 Katarzyna Macieszczak , Madalin Guta , Igor Lesanovsky , Juan P. Garrahan

We study the quantum Fisher information (QFI) of W states analytically with respect to SU(2) rotations in the basic decoherence channels i.e. depolarizing (DPC), amplitude damping (ADC) and phase damping (PDC), and present the interesting…

Quantum Physics · Physics 2016-02-16 Fatih Ozaydin

In this paper we provide the answer to the following question: given an arbitrary pure input state and a general, unbalanced, Mach-Zehnder interferometer, what transmission coefficient of the first beam splitter maximizes the quantum Fisher…

Quantum Physics · Physics 2022-01-17 Stefan Ataman

Recently new approaches for sensing the frequency of time dependent Hamiltonians have been presented, and it was shown that the optimal Fisher information scales as $T^{4}.$ We present here our interpretation of this new scaling, where the…

Quantum Physics · Physics 2017-09-13 Tuvia Gefen , Fedor Jelezko , Alex Retzker

The quantum Fisher information matrix is a central object in multiparameter quantum estimation theory. It is usually challenging to obtain analytical expressions for it because most calculation methods rely on the diagonalization of the…

Quantum Physics · Physics 2021-05-07 Lukas J. Fiderer , Tommaso Tufarelli , Samanta Piano , Gerardo Adesso

Quantum coherence is a central ingredient in quantum physics with several theoretical and technological ramifications. In this work we consider a figure of merit encoding the information on how the coherence generated on average by a…

A strange metal is an exotic state of correlated quantum matter; intensive efforts are ongoing to decipher its nature. Here we explore whether the quantum Fisher information (QFI), a concept from quantum metrology, can provide new insight.…

Strongly Correlated Electrons · Physics 2026-04-20 Federico Mazza , Sounak Biswas , Xinlin Yan , Andrey Prokofiev , Paul Steffens , Qimiao Si , Fakher F. Assaad , Silke Paschen