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Related papers: Quantum metrology and coherence

200 papers

Quantifying coherence is an essential endeavour for both quantum foundations and quantum technologies. Here the robustness of coherence is defined and proven a full monotone in the context of the recently introduced resource theories of…

We show that the quantum description of measurement based on decoherence fixes the bug in quantum theory discussed in [D. Frauchiger and R. Renner, {\em Quantum theory cannot consistently describe the use of itself}, Nat. Comm. {\bf 9},…

Quantum Physics · Physics 2018-10-17 Armando Relaño

We provide efficient and intuitive tools for deriving bounds on achievable precision in quantum enhanced metrology based on the geometry of quantum channels and semi-definite programming. We show that when decoherence is taken into account,…

Quantum Physics · Physics 2012-09-19 Rafal Demkowicz-Dobrzanski , Jan Kolodynski , Madalin Guta

A measurement is deemed successful, if one can maximize the information gain by the measurement apparatus. Here, we ask if quantum coherence of the system imposes a limitation on the information gain during quantum measurement. First, we…

Quantum Physics · Physics 2020-04-02 Gautam Sharma , Sk Sazim , Arun Kumar Pati

The original purpose of measurements is to provide us with information about a previously unknown physical property of the system observed. In the Hilbert space formalism of quantum mechanics, this physical meaning of measurement…

Quantum Physics · Physics 2007-05-23 Holger F. Hofmann , Takayoshi Kobayashi , Akira Furusawa

We examine a family of intrinsic performance measures in terms of probability distributions that generalize Hellinger distance and Fisher information. They are applied to quantum metrology to assess the uncertainty in the detection of…

Quantum Physics · Physics 2015-03-20 Alfredo Luis , Alfonso Rodil

Quantum addition channels have been recently introduced in the context of deriving entropic power inequalities for finite dimensional quantum systems. We prove a reverse entropy power equality which can be used to analytically prove an…

Quantum Physics · Physics 2026-04-13 Chiranjib Mukhopadhyay , Arun Kumar Pati , Sk Sazim

We introduce a procedure based on quantum expectation values of measurement observables to characterize quantum coherence. Our measure allows one to quantify coherence without having to perform tomography of the quantum state, and can be…

The uncertainty relation is a distinctive characteristic of quantum theory. The uncertainty is essentially rooted in quantum states. In this work we regard the uncertainty as an intrinsic property of quantum state and characterize it…

Quantum Physics · Physics 2024-05-31 Ming-Jing Zhao , Yuanhong Tao

Coherence arises from the superposition principle and plays a key role in quantum mechanics. Recently, Baumgratz et al. [T. Baumgratz, M. Cramer, and M. B. Plenio, Phys. Rev. Lett. 113, 140401 (2014)] established a rigorous framework for…

Quantum Physics · Physics 2016-03-23 Jianwei Xu

The goal of quantum metrology is to improve measurements' sensitivities by harnessing quantum resources. Metrologists often aim to maximize the quantum Fisher information, which bounds the measurement setup's sensitivity. In studies of…

Quantum metrology is deeply connected to quantum geometry, through the fundamental notion of quantum Fisher information. Inspired by advances in topological matter, it was recently suggested that the Berry curvature and Chern numbers of…

Quantum Physics · Physics 2024-11-12 Min Yu , Xiangbei Li , Yaoming Chu , Bruno Mera , F. Nur Ünal , Pengcheng Yang , Yu Liu , Nathan Goldman , Jianming Cai

In this paper the relation between quantum covariances and quantum Fisher informations are studied. This study is applied to generalize a recently proved uncertainty relation based on quantum Fisher information. The proof given…

Mathematical Physics · Physics 2007-12-10 Paolo Gibilisco , Fumio Hiai , Denes Petz

Quantum metrology enhances the sensitivity of parameter estimation using the distinctive resources of quantum mechanics such as entanglement. It has been shown that the precision of estimating an overall multiplicative factor of a…

Quantum Physics · Physics 2016-05-31 Shengshi Pang , Todd A. Brun

Quantum coherence, incompatibility, and quantum correlations are fundamental features of quantum physics. A unified view of those features is crucial for revealing quantitatively their intrinsic connections. We define the relative quantum…

Quantum Physics · Physics 2017-05-30 Ming-Liang Hu , Heng Fan

We address open quantum systems out-of-equilibrium as effective quantum probes for the characterisation of their environment. We discuss estimation schemes for parameters driving a de-phasing evolution of the probe and then focus on qubits,…

Quantum Physics · Physics 2019-05-14 Sholeh Razavian , Matteo G. A. Paris

Decoherence is widely felt to have something to do with the quantum measurement problem, but getting clear on just what is made difficult by the fact that the "measurement problem", as traditionally presented in foundational and…

Quantum Physics · Physics 2015-06-03 David Wallace

In this paper, we inaugurate the field of quantum fair machine learning. We undertake a comparative analysis of differences and similarities between classical and quantum fair machine learning algorithms, specifying how the unique features…

Machine Learning · Computer Science 2021-07-23 Elija Perrier

We address the scattering of a quantum particle by a one-dimensional barrier potential over a set of discrete positions. We formalize the problem as a continuous-time quantum walk on a lattice with an impurity, and use the quantum Fisher…

Quantum Physics · Physics 2020-12-30 Francesco Zatelli , Claudia Benedetti , Matteo G. A. Paris

The quantum theory of decoherence plays an important role in a pragmatist interpretation of quantum theory. It governs the descriptive content of claims about values of physical magnitudes and offers advice on when to use quantum…

Quantum Physics · Physics 2012-07-30 Richard Healey