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Related papers: Channel Discord and Distortion

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Distributing quantum correlations to each node of a network is a key aspect of quantum networking. Here, we present a robust, physically motivated protocol by which global quantum correlations, as characterized by the discord, can be…

Quantum Physics · Physics 2025-01-15 Adam G. Hawkins , Hannah McAleese , Mauro Paternostro

We introduce measures of quantum coherence as the speed of evolution of a system under decoherence. That is, coherence is the ability to estimate a dephasing channel, quantified by the quantum Fisher information. We extend the analysis to…

Quantum Physics · Physics 2019-01-23 Benjamin Yadin , Pieter Bogaert , Cristian E. Susa , Davide Girolami

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

Measurements of Quantum Systems disturb their states. To quantify this non-classical characteristic, Zurek and Ollivier introduced the quantum discord, a quantum correlation which can be nonzero even when entanglement in the system is zero.…

Quantum Physics · Physics 2010-07-13 Asma Al-Qasimi , Daniel F. V. James

One of the defining differences between classical and quantum systems is how measurements affect them. Here, we compare the approaches of contextuality and quantum discord in capturing quantum correlations in special classes of two-qubit…

Quantum Physics · Physics 2022-08-11 Asma Al-Qasimi

In this work, we investigate the dynamics of quantum correlations captured by entropic and geometric measures of discord under the influence of dissipative channels for widely used two qubit X state with maximally mixed marginals.…

Quantum Physics · Physics 2022-05-31 Nitish Kumar Chandra , Sarang S. Bhosale , Prasanta K. Panigrahi

We investigate the dynamics of quantum and classical correlations in a system of two qubits under local colored-noise dephasing channels. The time evolution of a single qubit interacting with its own environment is described by a memory…

Quantum Physics · Physics 2011-06-22 L. Mazzola , J. Piilo , S. Maniscalco

We introduce a simple and efficient technique to verify quantum discord in unknown Gaussian states and a certain class of non-Gaussian states. We show that any separation in the peaks of the marginal distributions of one subsystem…

A highly entangled bipartite quantum state is more advantageous for the quantum dense coding protocol than states with low entanglement. Such a correspondence, however, does not exist even for pure quantum states in the multipartite domain.…

Quantum Physics · Physics 2014-08-26 Tamoghna Das , R. Prabhu , Aditi Sen De , Ujjwal Sen

It was recently discovered that the quantum correlations of a pair of disentangled qubits, as measured by the quantum discord, can increase solely because of their interaction with a local dissipative bath. Here, we show that a similar…

Quantum Physics · Physics 2012-02-10 Francesco Ciccarello , Vittorio Giovannetti

Suppose that $m$ senders want to transmit classical information to $n$ receivers with zero probability of error using a noisy multipartite communication channel. The senders are allowed to exchange classical, but not quantum, messages among…

Quantum Physics · Physics 2009-06-25 Runyao Duan , Yaoyun Shi

The inherent connection between noise and disturbance is one of the most fundamental features of quantum measurements. In the two well-known extreme cases a measurement either makes no disturbance but then has to be totally noisy or is as…

Quantum Physics · Physics 2014-01-08 Teiko Heinosaari , Takayuki Miyadera

We present a simple model of quantum communication where a noisy quantum channel may benefit from the addition of further noise at the decoding stage. We demonstrate enhancement of the classical information capacity of an amplitude damping…

Quantum Physics · Physics 2015-06-26 Garry Bowen , Stefano Mancini

Preserving quantum coherence is fundamental challenge in the field of quantum computation. Here, I investigate the frozen discord phenomenon and non-Markovianity for qubits experiencing local dephasing in a classical environment. The…

Quantum Physics · Physics 2020-11-10 Bin Yi

A bipartite quantum system in a mixed state can exhibit nonclassical correlations, which can go beyond quantum entanglement. While quantum discord is the standard measure of quantifying such general quantum correlations, the nonclassicality…

Quantum Physics · Physics 2017-06-21 Amandeep Singh , Arvind , Kavita Dorai

Quantum discord witnesses the nonclassicality of quantum states even when there is no entanglement in these quantum states. This type of quantum correlation also has some interesting and significant applications in quantum information…

Quantum Physics · Physics 2015-05-19 Mazhar Ali

The single-mode bosonic channel is addressed with classical interference in the modulation and with side information at the transmitter. This model can viewed as the quantum counterpart of the classical random-parameter Gaussian channel.…

Quantum Physics · Physics 2021-05-12 Uzi Pereg

We study the relative strength of classical and quantum correlations, as measured by discord, for two-qubit states. Quantum correlations appear only in the presence of classical correlations, while the reverse is not always true. We…

Quantum Physics · Physics 2011-01-17 Fernando Galve , Gian Luca Giorgi , Roberta Zambrini

Geometric quantum discord is a well-defined measure of quantum correlation if Schatten 1-norm (trace norm) is adopted as a distance measure. Here, we analytically investigate the dynamical behavior of the 1-norm geometric quantum discord…

Quantum Physics · Physics 2013-05-08 J. D. Montealegre , F. M. Paula , A. Saguia , M. S. Sarandy

We identify ambiguities in the available frameworks for defining quantum, classical, and total correlations as measured by discordlike quantifiers. More specifically, we determine situations for which either classical or quantum…

Quantum Physics · Physics 2014-12-10 F. M. Paula , A. Saguia , Thiago R. de Oliveira , M. S. Sarandy