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Related papers: Estimation of n non-identical unitary channels

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We study relaxations of entanglement-assisted quantum channel coding and establish that non-signaling assistance and a natural semi-definite programming relaxation\, -- \,termed meta-converse\, -- \,are equivalent in terms of success…

Quantum Physics · Physics 2025-10-08 Aadil Oufkir , Mario Berta

A set of all states of a bi-partite quantum system can be divided into subsets each of which contains states with the same degree of entanglement. In this paper we address a question whether local operations (without classical…

Quantum Physics · Physics 2007-07-31 Mario Ziman , Vladimir Buzek

Using convex optimization, we propose entanglement-assisted quantum error correction procedures that are optimized for given noise channels. We demonstrate through numerical examples that such an optimized error correction method achieves…

Quantum Physics · Physics 2010-10-28 Soraya Taghavi , Todd A. Brun , Daniel A. Lidar

We consider a generalization of the discrete memoryless channel, in which the channel probability distribution is replaced by a uniform distribution over clouds of channel output sequences. For a random ensemble of such channels, we derive…

Information Theory · Computer Science 2022-09-22 Sergey Tridenski , Anelia Somekh-Baruch

In recent years, various means of efficiently detecting changepoints in the univariate setting have been proposed, with one popular approach involving minimising a penalised cost function using dynamic programming. In some situations, these…

Methodology · Statistics 2018-10-09 S. O. Tickle , I. A. Eckley , P. Fearnhead , K. Haynes

Quantum entanglement is a key enabling ingredient in diverse applications. However, the presence of unwanted adversarial entanglement also poses challenges in many applications. In this paper, we explore methods to "break" quantum…

Quantum Physics · Physics 2024-02-26 Fernando G. Jeronimo , Pei Wu

Over the past decades, linear mixed models have attracted considerable attention in various fields of applied statistics. They are popular whenever clustered, hierarchical or longitudinal data are investigated. Nonetheless, statistical…

Methodology · Statistics 2021-09-20 Katarzyna Reluga , María José Lombardía , Stefan Andreas Sperlich

Entanglement plays a central role in quantum information processing, indicating the non-local correlation of quantum matters. However, few effective ways are known to detect the amount of entanglement of an unknown quantum state. In this…

Quantum Physics · Physics 2020-11-26 You Zhou , Pei Zeng , Zhenhuan Liu

We study the effect of fading in the communication channels between sensor nodes on the performance of the incremental least mean square (ILMS) algorithm, and derive steady state performance metrics, including the mean-square deviation…

Information Theory · Computer Science 2015-09-10 Azam Khalili , Amir Rastegarnia

We introduce a framework for the study of multiparty entanglement by analyzing the behavior of collective variables. Throughout the manuscript, we explore a specific type of multiparty entanglement which can be detected through the…

Quantum Physics · Physics 2025-05-19 Éloi Descamps , Arne Keller , Pérola Milman

Recently Galv\~{a}o and Hardy have shown that quantum cloning can improve the performance of some quantum computation tasks. However such performance enhancement is possible only if quantum correlations survive the cloning process. We…

Quantum Physics · Physics 2007-05-23 Paweł Masiak

We determine the optimal rates of universal quantum codes for entanglement transmission and generation under channel uncertainty. In the simplest scenario the sender and receiver are provided merely with the information that the channel…

Quantum Physics · Physics 2015-05-13 I. Bjelakovic , H. Boche , J. Noetzel

Instantaneous measurements of non-local observables between space-like separated regions can be performed without violating causality. This feat relies on the use of entanglement. Here we propose novel protocols for this task and the…

Quantum Physics · Physics 2015-05-20 Salman Beigi , Robert Koenig

This paper presents adaptive bidirectional minimum mean-square error parameter estimation algorithms for fast-fading channels. The time correlation between successive channel gains is exploited to improve the estimation and tracking…

Information Theory · Computer Science 2015-10-14 P. Clarke , R. C. de Lamare

This paper compares and evaluates a set of non-parametric mutual information estimators with the goal of providing a novel toolset to progress in the analysis of the capacity of the nonlinear optical channel, which is currently an open…

Information Theory · Computer Science 2018-01-25 Tommaso Catuogno , Menelaos Ralli Camara , Marco Secondini

An efficient method for assessing the quality of quantum state tomography is developed. Special attention is paid to the tomography of multipartite systems in terms of unbiased measurements. Although the overall reconstruction errors of…

Quantum Physics · Physics 2013-11-19 J. Rehacek , Z. Hradil , A. B. Klimov , G. Leuchs , L. L. Sanchez-Soto

We consider the distribution of high-dimensional entangled states to multiple parties via noisy channels and the subsequent probabilistic conversion of these states to desired target states using stochastic local operations and classical…

Quantum Physics · Physics 2022-06-01 Simon Morelli , David Sauerwein , Michalis Skotiniotis , Nicolai Friis

Computing entanglement of an arbitrary bipartite or multipartite mixed state is in general not an easy task as it usually involves complex optimization. Here we show that exploiting symmetries of certain mixed states, we can compute a…

Quantum Physics · Physics 2016-08-31 Tamoghna Das , Sudipto Singha Roy , Shrobona Bagchi , Avijit Misra , Aditi Sen De , Ujjwal Sen

Recently, machine learning-based channel estimation has attracted much attention. The performance of machine learning-based estimation has been validated by simulation experiments. However, little attention has been paid to the theoretical…

Signal Processing · Electrical Eng. & Systems 2021-07-15 Kai Mei , Jun Liu , Xiaochen Zhang , Nandana Rajatheva , Jibo Wei

We study the problem of simulating a two-user multiple-access channel (MAC) over a multiple access network of noiseless links. Two encoders observe independent and identically distributed (i.i.d.) copies of a source random variable each,…

Information Theory · Computer Science 2023-12-08 Gowtham R. Kurri , Viswanathan Ramachandran , Sibi Raj B. Pillai , Vinod M. Prabhakaran