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Related papers: Fidelity balance in quantum operations

200 papers

Quantum state comparison, utilizing metrics like fidelity and trace distance, underpins the assessment of quantum networks within quantum information theory. While recent research has expanded theoretical understanding, incorporating error…

Quantum Algebra · Mathematics 2024-04-18 John T. M. Campbell , Nicola Marchetti , John Dooley , Indrakshi Dey

We show the flaws found in the customary fidelity-based definitions of disturbance in quantum measurements and evolutions. We introduce the "entropic disturbance" D and show that it adequately measures the degree of disturbance, intended…

Quantum Physics · Physics 2009-11-13 Lorenzo Maccone

Claims of successful quantum teleportation are backed up by showing that fidelity exceeds some specified threshold, but whether fidelity is the performance metric and what the threshold should be has been a subject of vigorous debate. We…

Quantum Physics · Physics 2026-04-21 Nehad AttaElmanan AbdElrahim Mabrouk , Barry C Sanders

Quantum information technologies require careful control for generating and preserving a desired target quantum state. The biggest practical obstacle is, of course, decoherence. Therefore, the reachability analysis, which in our scenario…

Quantum Physics · Physics 2019-05-30 Kohei Kobayashi , Naoki Yamamoto

To implement quantum information technologies, carefully designed control for preparing a desired state plays a key role. However, in realistic situation, the actual performance of those methodologies is severely limited by decoherence.…

Quantum Physics · Physics 2025-10-02 Kohei Kobayashi

We analyze approximate transformations of pure entangled quantum states by local operations and classical communication, finding explicit conversion strategies which optimize the fidelity of transformation. These results allow us to…

Quantum Physics · Physics 2009-10-31 Guifre Vidal , Daniel Jonathan , M. A. Nielsen

Permitting the transmission of unknown quantum states over long distances by using entanglement, quantum teleportation serves as an important building block for many quantum technologies. However, in the noisy intermediate-scale quantum…

Quantum Physics · Physics 2024-07-17 Zi-Jian Xu , Jun-Hong An

Causal order can improve the quantum information transmission in teleportation due a noisy entangled resource by using an appropriate measurement state on the control state ruling the causal order. In this work, we get analytically the…

Quantum Physics · Physics 2020-10-13 Carlos Cardoso-Isidoro , Francisco Delgado

We experimentally demonstrate quantum teleportation for continuous variables using squeezed-state entanglement. The teleportation fidelity for a real experimental system is calculated explicitly, including relevant imperfection factors such…

Quantum Physics · Physics 2009-11-07 T. C. Zhang , K. W. Goh , C. W. Chou , P. Lodahl , H. J. Kimble

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

Various aspects of distillation of noisy entanglement and some associated effects in quantum error correction are considered. In particular we prove that if only one--way classical communication (from Alice to Bob) is allowed and the shared…

Quantum Physics · Physics 2009-11-11 Pawel Horodecki , Maciej Demianowicz

Recently it has been argued that all presently performed continuous variable quantum teleportation experiments could be explained using a local hidden variable theory. In this paper we study a modification of the original protocol which…

Quantum Physics · Physics 2007-08-04 Aurel Gabris , Girish S. Agarwal

Fidelity and relative entropy are two significant quantities in quantum information theory. We study the quantum fidelity and relative entropy under unitary orbits. The maximal and minimal quantum fidelity and relative entropy between two…

Quantum Physics · Physics 2014-01-15 Lin Zhang , Shao-Ming Fei

To explore the properties of a two-qubit mixed state, we consider quantum teleportation. The fidelity of a teleported state depends on the resource state purity and entanglement, as characterized by concurrence. Concurrence and purity are…

Quantum Physics · Physics 2018-10-30 Sumit Nandi , Chandan Datta , Arpan Das , Pankaj Agrawal

The conventional certification method for quantum teleportation protocols relies on surpassing the highest achievable classical average fidelity between target and teleported states. Our investigation highlights the limitations of this…

Quantum Physics · Physics 2025-06-06 D. G. Bussandri , G. M. Bosyk , F. Toscano

Teleportation for pure states, mixed states with standard and optimal protocols are introduced and investigated systematically. An explicit equation governing the teleportation of finite dimensional quantum pure states by a generally given…

Quantum Physics · Physics 2007-05-23 S. Albeverio , S. M. Fei , W. L. Yang

We study quantum teleportation via Bell-diagonal mixed states of two qubits in the context of the intrinsic properties of the quantum discord. We show that when the quantum-correlated state of the two qubits is used for quantum…

Quantum Physics · Physics 2015-11-05 Katarzyna Roszak , Łukasz Cywiński

I report a tight upper bound of the maximum speed of evolution from one quantum state $\rho$ to another $\rho'$ with fidelity $F(\rho,\rho')$ less than or equal to an arbitrary but fixed value under the action of a time-independent…

Quantum Physics · Physics 2013-05-29 H. F. Chau

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

The dynamics of entangled state interacting with a single cavity mode is investigated in the presence of a random parameter. We have shown that degree of entanglement decays with time and rate of decay is defined by features of random…

Quantum Physics · Physics 2010-09-28 N. Metwally , L. Chotorlishvili , V. Skrinnikov