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Related papers: A fidelity measure for quantum channels

200 papers

We relate gate fidelities of experimentally realized quantum operations to the broadcasting property of their ideal operations, and show that the more parties a given quantum operation can broadcast to, the higher gate fidelities of its…

Quantum Physics · Physics 2011-06-30 Hyang-Tag Lim , Young-Sik Ra , Yong-Su Kim , Yoon-Ho Kim , Joonwoo Bae

In this paper, we introduce the framework for quantifying the imaginarity of quantum channels. Besides, an alternative framework is given together to simplify the process of verifying the condition. We present three imaginarity measures of…

Quantum Physics · Physics 2025-02-25 Xiangyu Chen , Qiang Lei

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

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 analyze mean fidelity between random density matrices of size N, generated with respect to various probability measures in the space of mixed quantum states: Hilbert-Schmidt measure, Bures (statistical) measure, the measures induced by…

Quantum Physics · Physics 2009-11-10 Karol Zyczkowski , Hans-Jurgen Sommers

The entanglement fidelity provides a measure of how well the entanglement between two subsystems is preserved in a quantum process. By using a simple model we show that in some cases this quantity in its original definition fails in the…

Quantum Physics · Physics 2009-11-13 Yang Xiang , Shi-Jie Xiong

Protocols for discriminating between a pair of channels or for estimating a channel parameter can often be aided by adaptivity or by entanglement between the probe states. This can make it difficult to bound the best possible performance…

Quantum Physics · Physics 2021-10-07 Jason L. Pereira , Leonardo Banchi , Stefano Pirandola

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

The fidelity (Shannon mutual information between measurements and physical quantities) is proposed as a quantitative measure of the quality of physical measurements. The fidelity does not depend on the true value of unknown physical…

Quantum Physics · Physics 2011-03-15 Thomas B. Bahder

We analyze the quality of the quantum information transmission along a correlated quantum channel by studying the average fidelity between input and output states and the average output purity, giving bounds for the entropy of the channel.…

Quantum Physics · Physics 2008-11-26 Davide Rossini , Vittorio Giovannetti , Simone Montangero

We provide new results for computing and comparing the quantum gate fidelity of quantum channels via their Choi matrices. We extend recent work that showed there exist non-dual pairs of quantum channels with equal gate fidelity by providing…

Quantum Physics · Physics 2012-03-06 Nathaniel Johnston , David W. Kribs

We introduce the concept of quasi-inverse of quantum and classical channels, prove general properties of these inverses and determine them for a large class of channels acting in an arbitrary finite dimension. Therefore we extend the…

Quantum Physics · Physics 2021-08-11 Fereshte Shahbeigi , Koorosh Sadri , Morteza Moradi , Karol Życzkowski , Vahid Karimipour

We consider several definitions of the quantum Wasserstein distance based on an optimization over general bipartite quantum states with given marginals. Then, we examine the quantities obtained after the optimization is carried out over…

Quantum Physics · Physics 2026-05-15 Géza Tóth , József Pitrik

Fidelity is a figure of merit widely employed in quantum technology in order to quantify similarity between quantum states and, in turn, to assess quantum resources or reconstruction techniques. Fidelities higher than, say, 0.9 or 0.99, are…

Quantum Physics · Physics 2015-06-17 Matteo Bina , Antonio Mandarino , Stefano Olivares , Matteo G. A. Paris

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 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

Entanglement fidelity quantifies how well a quantum channel preserves the correlations between a transmitted system and an inaccessible reference system. We derive closed-form expressions for the entanglement fidelity associated with…

Quantum Physics · Physics 2026-03-10 Niccolò Zanieri , Marios Kountouris

Quantum state transfer protocols are a major toolkit in many quantum information processing tasks, from quantum key distribution to quantum computation. To assess performance of a such a protocol, one often relies on the average fidelity…

In this paper we provide a novel way to explore the relation between quantum teleportation and quantum phase transition. We construct a quantum channel with a mixed state which is made from one dimensional quantum Ising chain with infinite…

Quantum Physics · Physics 2018-05-03 Meng-He Wu , Yi Ling , Fu-Wen Shu , Wen-Cong Gan

Two measures of sensitivity to eavesdropping for alphabets of quantum states were recently introduced by Fuchs and Sasaki in quant-ph/0302092. These are the accessible fidelity and quantumness. In this paper we prove an important property…

Quantum Physics · Physics 2007-05-23 K. M. R. Audenaert , C. A. Fuchs , C. King , A. Winter