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Related papers: Classical Optical Analogue of Quantum Discord

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Among various definitions of quantum correlations, quantum discord has attracted considerable attention. To find analytical expression of quantum discord is an intractable task. Exact results are known only for very special states, namely,…

Quantum Physics · Physics 2015-05-27 Mingjun Shi , Fengjian Jiang , Chunxiao Sun , Jiangfeng Du

In the last years the exploitation of specific properties of quantum states has disclosed the possibility of realising tasks beyond classical limits, creating the new field of quantum technologies [1, 2, 3, 4, 5, 6, 7, 8, 9]. Among them,…

Quantum Physics · Physics 2015-06-16 E. D. Lopaeva , I. Ruo Berchera , S. Olivares , G. Brida , I. P. Degiovanni , M. Genovese

Much of the richness in nature arises due to the connection between classical and quantum mechanics. In advanced science, the tools of quantum mechanics was not only applied in microscopic description but also found its efficacy in…

Optics · Physics 2021-04-15 Zhaoyang Wang , Ziyu Zhan , Xing Fu , Yijie Shen

We investigate the quantum advantage in quantum illumination using two-qubit mixed states as the initial resource. We show that in quantum illumination, the achievable advantage is determined by an interplay between initial entanglement and…

Quantum Physics · Physics 2026-02-11 Mojtaba Asadollahi , Mohammad Hossein Zarei

Quantum discord (QD) reveals the nonclassical nature of correlations in bipartite quantum states, going beyond the entanglement-separability paradigm. In this article we discuss the suitability of QD in what concern its possible asymmetry…

Quantum Physics · Physics 2015-03-14 J. Maziero , L. C. Celeri , R. M. Serra

Quantum discord is a measure of non-classical correlations, which are excess correlations inherent in quantum states that cannot be accessed by classical measurements. For multipartite states, the classically accessible correlations can be…

Quantum Physics · Physics 2019-09-18 Mark Bradshaw , Ping Koy Lam , Syed M. Assad

High-dimensional entanglement with spatial modes of light promises increased security and information capacity over quantum channels. Unfortunately, entanglement decays due to perturbations, corrupting quantum links which cannot be repaired…

A quantum state is called concordant if it has zero quantum discord with respect to any part. By extension, a concordant computation is one such that the state of the computer, at each time step, is concordant. In this paper, I describe a…

Quantum Physics · Physics 2010-06-24 Bryan Eastin

Quantum discord characterizes "non-classicality" of correlations in quantum mechanics. It has been proposed as the key resource present in certain quantum communication tasks and quantum computational models without containing much…

Quantum Physics · Physics 2010-11-04 Borivoje Dakic , Vlatko Vedral , Caslav Brukner

We study the level surfaces of quantum discord for a class of two-qubit states with parallel nonzero Bloch vectors. The dynamic behavior of quantum discord under decoherence is investigated. It is shown that a class of X states has sudden…

Quantum Physics · Physics 2011-04-12 Bo Li , Zhi-Xi Wang , Shao-Ming Fei

We demonstrate that a tensor product structure and optical analogy of quantum entanglement can be obtained by introducing pseudorandom phase sequences into classical fields with two orthogonal modes. Using the classical analogy, we discuss…

Quantum Physics · Physics 2016-09-27 Jian Fu , Xutai Ma , Wenjiang Li , Shuo Sun

We study the dynamics of classical correlation, quantum discord and measurement-induced disturbance of Dirac fields in the background of a dilaton black hole. We present an alternative physical interpretation of single mode approximation…

Quantum Physics · Physics 2014-12-31 Jieci Wang , Jiliang Jing , Heng Fan

Niels Bohr proposed that the outcome of the measurement becomes objective and real, and, hence, classical, when its results can be communicated by classical means. In this work we revisit Bohr's postulate using modern tools from the quantum…

Quantum Physics · Physics 2013-07-24 Alexander Streltsov , Wojciech H. Zurek

Quantum discord measures quantum correlation by comparing the quantum mutual information with the maximal amount of mutual information accessible to a quantum measurement. This paper analyzes the properties of diagonal discord, a simplified…

Quantum Physics · Physics 2019-03-04 Zi-Wen Liu , Ryuji Takagi , Seth Lloyd

This paper summarizes the basics of the notion of quantum discord and how it relates to other types of correlations in quantum physics. We take the fundamental information theoretic approach and illustrate our exposition with a number of…

Quantum Physics · Physics 2017-02-07 Vlatko Vedral

Quantum discord plays a pragmatic role in analyzing nonclassical feature of quantum correlations beyond entanglement. It is used in several information processing protocols which lacks sufficient amount of entanglement to be used as a…

Quantum Physics · Physics 2019-10-02 Kaushiki Mukherjee , Sumana Karmakar , Biswajit Paul , Debasis Sarkar

We investigate the disappearance of discord in 2- and multi-qubit systems subject to decohering influences. We formulate the computation of quantum discord in terms of the generalized Bloch vector, which gives useful insights on the time…

Quantum Physics · Physics 2014-04-21 Hyungjun Lim , Robert Joynt

The power of quantum computers is still somewhat speculative. While they are certainly faster than classical ones at some tasks, the class of problems they can efficiently solve has not been mapped definitively onto known classical…

Quantum Physics · Physics 2020-07-09 N. H. Nguyen , E. C. Behrman , M. A. Moustafa , J. E. Steck

Classical optical interference experiments correspond to a measurement of the first-order correlation function of the electromagnetic field. The converse of this statement: experiments that measure the first order correlation functions do…

Quantum Physics · Physics 2009-11-07 Ole Steuernagel

Quantum computers and quantum algorithms have made great strides in the last few years and promise improvements over classical computing for specific tasks. Although the current hardware is not yet ready to make real impacts at the time of…

Quantum Physics · Physics 2024-08-28 Nils Quetschlich , Tobias Forster , Adrian Osterwind , Domenik Helms , Robert Wille