English
Related papers

Related papers: Fidelity for Multimode Thermal Squeezed States

200 papers

Fidelity estimation for entangled states constitutes an essential building block for quality control and error detection in quantum networks. Nonetheless, quantum networks often encounter heterogeneous and correlated noise, leading to…

Quantum Physics · Physics 2024-11-18 Liangzhong Ruan , Bas Dirkse

Quantum communication networks can be built on quantum teleportation, which is the transmission of an unknown quantum state from a sending station to a remote receiving station supported by entangled states and classical communication. We…

To establish an entangled state of optimal fidelity between two distant observers when the available quantum channel is noisy, is a central problem in quantum information theory. We consider an instance of this problem for two-qubit systems…

Quantum Physics · Physics 2012-09-18 Somshubhro Bandyopadhyay , Anindita Ghosh

We investigate quantum teleportation through noisy quantum channels by solving analytically and numerically a master equation in the Lindblad form. We calculate the fidelity as a function of decoherence rates and angles of a state to be…

Quantum Physics · Physics 2009-11-07 Sangchul Oh , Soonchil Lee , Hai-woong Lee

Quantum teleportation is one of the essential primitives of quantum communication. We suggest that any quantum teleportation scheme can be characterized by its efficiency, i.e. how often it succeeds to teleport, its fidelity, i.e. how well…

Quantum Physics · Physics 2015-06-26 Dik Bouwmeester , Jian-Wei Pan , Harald Weinfurter , Anton Zeilinger

We derive the exact expression for the Uhlmann fidelity between arbitrary thermal Gibbs states of the quantum XY model in a transverse field with finite system size. Using it, we conduct a thorough analysis of the fidelity susceptibility of…

Quantum Physics · Physics 2021-09-24 Michał Białończyk , Fernando Javier Gómez-Ruiz , Adolfo del Campo

We first derive for the general form of the fidelity for various bosonic channels. Thereby we give the fidelity of different quantum bosonic channel, possibly with product input and entangled input respectively, as examples. The properties…

Quantum Physics · Physics 2009-11-13 Meisheng Zhao , Tao Qin , Yongde Zhang

We study the fidelity approach to quantum phase transitions (QPTs) and apply it to general thermal phase transitions (PTs). We analyze two particular cases: the Stoner-Hubbard itinerant electron model of magnetism and the BCS theory of…

Quantum Physics · Physics 2009-11-13 Nikola Paunkovic , Vitor Rocha Vieira

A general framework for analyzing the recently discovered phase transitions in the steady state of dissipation-driven open quantum systems is still missing. In order to fill this gap we extend the so-called fidelity approach to quantum…

Quantum Physics · Physics 2014-02-12 Leonardo Banchi , Paolo Giorda , Paolo Zanardi

Estimating the fidelity of state preparation in multi-qubit systems is generally a time-consuming task. Nevertheless, this complexity can be reduced if the desired state can be characterized by certain symmetries measurable with the…

Quantum Physics · Physics 2009-11-13 R. D. Somma , J. Chiaverini , D. J. Berkeland

In this paper we discuss the fidelity of states in infinite dimensional systems, give an elementary proof of the infinite dimensional version of Uhlmann's theorem, and then, apply it to generalize several properties of the fidelity from…

Quantum Physics · Physics 2011-07-05 Jinchuan Hou , Xiaofei Qi

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

We consider the standard quantum teleportation protocol where a general bipartite state is used as entanglement resource. We use the entanglement fidelity to describe how well the standard quantum teleportation channel transmits quantum…

Quantum Physics · Physics 2015-06-05 Gang Li , Ming-Yong Ye , Xiu-Min Lin

We derive a general limit on the fidelity of a quantum channel conveying an ensemble of pure states. Unlike previous results, this limit applies to arbitrary coding and decoding schemes, including nonunitary decoding. This establishes the…

Quantum Physics · Physics 2016-09-08 Howard Barnum , Christopher A. Fuchs , Richard Jozsa , Benjamin Schumacher

Here, a physical formalism is proposed for an unconditional microwave quantum teleportation of Gaussian states via two-mode squeezed states in lossy environments. The proposed formalism is controllable to be used in both the fridge and free…

Quantum Physics · Physics 2021-03-05 Vahid Salari

We introduce a family of quantum R\'enyi fidelities and discuss their symmetry resolution. We express the symmetry-resolved fidelities as Fourier transforms of charged fidelities, for which we derive exact formulas for Gaussian states.…

Statistical Mechanics · Physics 2022-12-02 Gilles Parez

A bipartite quantum state is tomographically faithful when it can be used as an input of a quantum operation acting on one of the two quantum systems, such that the joint output state carries a complete information about the operation…

Quantum Physics · Physics 2009-11-11 G. M. D'Ariano , M. F. Sacchi

We consider quantum fidelity between two states $\rho$ and $\sigma$, where we fix $\rho$ and allow $\sigma$ to be sent through a quantum channel. We determine the minimal fidelity where one minimizes over (a) all unital channels, (b) all…

Quantum Physics · Physics 2015-09-11 Jin Li , Rajesh Pereira , Sarah Plosker

Distinguishable and non-distinguishable quantum states are fundamental resources in quantum mechanics and quantum technologies. Interactions with the environment often induce decoherence, impacting both the distinguishability and…

Quantum Physics · Physics 2026-04-28 Kai Liu , Deguang Han

In this thesis we focus on Gaussian quantum metrology in the phase-space formalism and its applications in quantum sensing and the estimation of space-time parameters. We derive new formulae for the optimal estimation of multiple parameters…

Quantum Physics · Physics 2016-10-13 Dominik Šafránek