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Related papers: Multivariate Fidelities

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The measures of distances between points in a Hilbert space are one of the basic theoretical concepts used to characterize properties of a quantum system with respect to some etalon state. These are not only used in studying fidelity of…

Quantum Physics · Physics 2019-04-03 Karol Bartkiewicz , Vojtěch Trávníček , Karel Lemr

We study the quantum fidelity (groundstate overlap) near quantum phase transitions of the Ising universality class in one dimensional (1D) systems of finite size L. Prominent examples occur in magnetic systems (e.g. spin-Peierls, the…

Mesoscale and Nanoscale Physics · Physics 2016-06-30 E. J. König , A. Levchenko , N. Sedlmayr

We introduce a multi-fidelity estimator of covariance matrices that employs the log-Euclidean geometry of the symmetric positive-definite manifold. The estimator fuses samples from a hierarchy of data sources of differing fidelities and…

Computation · Statistics 2023-05-30 Aimee Maurais , Terrence Alsup , Benjamin Peherstorfer , Youssef Marzouk

We study ground state fidelity defined as the overlap between two ground states of the same quantum system obtained for slightly different values of the parameters of its Hamiltonian. We focus on the thermodynamic regime of the XY model and…

Quantum Physics · Physics 2015-03-19 Marek M. Rams , Bogdan Damski

We study fidelity susceptibility in one-dimensional asymmetric Hubbard model, and show that the fidelity susceptibility can be used to identify the universality class of the quantum phase transitions in this model. The critical exponents…

Quantum Physics · Physics 2009-11-13 Shi-Jian Gu , Ho-Man Kwok , Wen-Qiang Ning , Hai-Qing Lin

This paper initiates the study of hidden variables from the discrete, abstract perspective of quantum computing. For us, a hidden-variable theory is simply a way to convert a unitary matrix that maps one quantum state to another, into a…

Quantum Physics · Physics 2013-05-29 Scott Aaronson

We introduce the concept of fidelity for dynamical maps in an open quantum system scenario. We derive an inequality linking this quantity to the distinguishability of the inducing environmental states. Our inequality imposes constraints on…

Quantum Physics · Physics 2017-05-10 Mikko Tukiainen , Henri Lyyra , Gniewomir Sarbicki , Sabrina Maniscalco

We demonstrate a sequence of two quantum teleportations of optical coherent states, combining two high-fidelity teleporters for continuous variables. In our experiment, the individual teleportation fidelities are evaluated as F_1 = 0.70 \pm…

Quantum Physics · Physics 2009-11-13 Hidehiro Yonezawa , Akira Furusawa , Peter van Loock

Fidelity is crucial for characterizing transformations of quantum states under various quantum channels, which can be served as a fundamental tool in resource theories. Firstly, we define an $\alpha$-$z$-fidelity as a significant quantity…

Quantum Physics · Physics 2025-07-08 Xiaojing Yan , Xiao Sun , Mingming Du , Jiashan Tang

Josza's definition of fidelity for a pair of (mixed) quantum states is studied in the context of two types of operator algebras. The first setting is mainly algebraic in that it involves unital C$^*$-algebras $A$ that possess a faithful…

Quantum Physics · Physics 2016-11-23 Douglas Farenick , Samuel Jaques , Mizanur Rahaman

We investigate quantum teleportation of ensembles of coherent states of light with a Gaussian distributed displacement in phase space. Recently, the following general question has been addressed in [P. Liuzzo-Scorpo et al.,…

Quantum Physics · Physics 2017-11-29 Pietro Liuzzo-Scorpo , Gerardo Adesso

We investigate the problem of bounding the quantum process fidelity given bounds on the fidelities between target states and the action of a process on a set of pure input states. We formulate the problem as a semidefinite program and prove…

Quantum Physics · Physics 2018-11-28 Karl Mayer , Emanuel Knill

Quantum state discrimination is a fundamental concept in quantum information theory, which refers to a class of techniques to identify a specific quantum state through a positive operator-valued measure. In this work, we investigate how…

Quantum Physics · Physics 2025-07-09 Hyunho Cha , Jungwoo Lee

Generative models are increasingly deployed as substitutes for real data in downstream scientific workflows, yet standard evaluation criteria remain focused on marginal distribution matching. We argue that this represents a fundamental gap:…

Machine Learning · Statistics 2026-05-19 Nazia Riasat

Continuous-variable (CV) quantum teleportation is usually benchmarked by average fidelity, but when the teleportation is repeatedly used within optical networks or measurement-based architectures, uniformity across the input ensemble…

Quantum Physics · Physics 2026-04-23 Kyoungho Cho , Bongjune Kim , Jeongho Bang

We study the problem of universal quantum cloning -- taking several identical copies of a pure but unknown quantum state and producing further copies. While it is well known that it is impossible to perfectly reproduce the state, how well…

Quantum Physics · Physics 2016-08-09 Alastair Kay

It is known that the quantum fidelity, as a measure of the closeness of two quantum states, is operationally equivalent to the minimal overlap of the probability distributions of the two states over all possible POVMs; the POVM realizing…

Quantum Physics · Physics 2009-11-10 Hyunchul Nha , H. J. Carmichael

This document focuses on translating various information-theoretic measures of distinguishability for probability distributions into measures of distin- guishability for quantum states. These measures should have important appli- cations in…

Quantum Physics · Physics 2007-05-23 Christopher A. Fuchs

We consider a single copy of a mixed state of two qubits and show how its fidelity or maximal singlet fraction is related to the entanglement measures concurrence and negativity. We characterize the extreme points of the convex set of…

Quantum Physics · Physics 2009-11-07 Frank Verstraete , Henri Verschelde

We investigate generalized measurements, based on positive-operator-valued measures, and von Neumann measurements for the unambiguous discrimination of two mixed quantum states that occur with given prior probabilities. In particular, we…

Quantum Physics · Physics 2009-11-11 Ulrike Herzog , Janos A. Bergou
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