Results 31 to 40 of about 142,025 (180)
Results in Physics, 2023 In post-selection quantum measurement, it is a dilemma to obtain both high precision and large post-selection probability. Here,we deeply examine quantum Fisher information and probability of post-selection quantum measurement based on the trapped ion ...
He-fei Li +6 more
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Quantum Fisher information with coherence
Optica, 2019 In recent proposals for achieving optical super-resolution, variants of the Quantum Fisher Information (QFI) quantify the attainable precision. We find that claims about a strong enhancement of the resolution resulting from coherence effects are questionable because they refer to very small subsets of the data without proper normalization. When the QFI
Zdeněk Hradil +3 more
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Multipartite entanglement of the topologically ordered state in a perturbed toric code
Physical Review Research, 2022 We demonstrate that multipartite entanglement, witnessed by the quantum Fisher information, can characterize topological quantum phase transitions in the spin-1/2 toric code model (TCM) on a square lattice with external fields.
Yu-Ran Zhang +5 more
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Multi-parameter estimation beyond quantum Fisher information [PDF]
Journal of Physics A: Mathematical and Theoretical, 2020 This review aims at gathering the most relevant quantum multi-parameter estimation methods that go beyond the direct use of the Quantum Fisher Information concept. We discuss in detail the Holevo Cram r-Rao bound, the Quantum Local Asymptotic Normality approach as well as Bayesian methods.
Rafał Demkowicz-Dobrzański +2 more
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From ƒ-Divergence to Quantum Quasi-Entropies and Their Use
Entropy, 2010 Csiszár’s ƒ-divergence of two probability distributions was extended to the quantum case by the author in 1985. In the quantum setting, positive semidefinite matrices are in the place of probability distributions and the quantum generalization is called ...
Dénes Petz
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Probing cosmic string spacetime through parameter estimation
European Physical Journal C: Particles and Fields, 2022 Quantum metrology studies the ultimate precision limit of physical quantities by using quantum strategy. In this paper we apply the quantum metrology technologies to the relativistic framework for estimating the deficit angle parameter of cosmic string ...
Ying Yang, Jiliang Jing, Zehua Tian
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Fidelity and Fisher information on quantum channels
New Journal of Physics, 2017 The fidelity function for quantum states has been widely used in quantum information science and frequently arises in the quantification of optimal performances for the estimation and distinguishing of quantum states.
Haidong Yuan, Chi-Hang Fred Fung
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Metrology and multipartite entanglement in measurement-induced phase transition [PDF]
QuantumMeasurement-induced phase transition arises from the competition between a deterministic quantum evolution and a repeated measurement process. We explore the measurement-induced phase transition through the Quantum Fisher Information in two different ...
Giovanni Di Fresco +3 more
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Fisher information as a probe of spacetime structure: relativistic quantum metrology in (A)dS
Journal of High Energy Physics, 2021 Relativistic quantum metrology studies the maximal achievable precision for estimating a physical quantity when both quantum and relativistic effects are taken into account.
Haoxing Du, Robert B. Mann
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Simultaneous Perturbation Stochastic Approximation of the Quantum Fisher Information [PDF]
Quantum, 2021 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.
Julien Gacon +3 more
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