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Related papers: Geometric Quantum Discord Signals Non-Factorizatio…

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We check the decoherence dynamics of Measurement-induced Nonlocality(in short, MIN) and compare it with geometric discord for two qubit systems. There are quantum states, on which the action of dephasing channel cannot destroy MIN in finite…

Quantum Physics · Physics 2014-05-15 Ajoy Sen , Debasis Sarkar , Amit Bhar

We introduce the notion of quantum dissension for a three-qubit system as a measure of quantum correlations. We use three equivalent expressions of three-variable mutual information. Their differences can be zero classically but not so in…

Quantum Physics · Physics 2012-04-05 Indranil Chakrabarty , Pankaj Agrawal , Arun K. Pati

We investigate and compare three distinguished geometric measures of bipartite quantum correlations that have been recently introduced in the literature: the geometric discord, the measurement-induced geometric discord, and the discord of…

Quantum Physics · Physics 2016-05-26 Wojciech Roga , Dominique Spehner , Fabrizio Illuminati

Quantum discord, as introduced by Olliver and Zurek [Phys. Rev. Lett. \textbf{88}, 017901 (2001)], is a measure of the discrepancy between quantum versions of two classically equivalent expressions for mutual information and is found to be…

Quantum Physics · Physics 2015-06-04 Ali Saif M. Hassan , Pramod S. Joag

Quantum discord is a function of density-matrix elements (and through them, e.~g., of temperature, applied fields, time, and so forth). The domain of such a function in the case of two-qubit system with X or centrosymmetric (CS) density…

Quantum Physics · Physics 2014-04-24 M. A. Yurischev

The ground state of a quantum spin chain is a natural playground for investigating correlations. Nevertheless, not all correlations are genuinely of quantum nature. Here we review the recent progress to quantify the 'quantumness' of the…

Quantum Physics · Physics 2015-03-20 Marcelo S. Sarandy , Thiago R. de Oliveira , Luigi Amico

Multipartite quantum systems show properties which do not admit a classical explanation. In particular, even nonentangled states can enjoy a kind of quantum correlations called quantum discord. I discuss some recent results on the role of…

Quantum Physics · Physics 2015-11-04 Davide Girolami

We propose a new criterion to judge zero quantum discord for arbitrary bipartite states. A bipartite quantum state has zero quantum discord if and only if all blocks of its density matrix are normal matrices and commute with each other.…

Quantum Physics · Physics 2015-03-19 Jie-Hui Huang , Lei Wang , Shi-Yao Zhu

Quantum discord, a key indicator of non-classical correlations in bipartite systems, has been recently extended to multipartite scenarios [Phys. Rev. Lett. 2020, 124:110401]. We present exact analytic formulas for the quantum discord of…

Quantum Physics · Physics 2025-03-21 Jianming Zhou , Xiaoli Hu , Honglian Zhang , Naihuan Jing

Gaussian quantum discord is a measure of quantum correlations in Gaussian systems. Using Gaussian discord we quantify the quantum correlations of a bipartite entangled state and a separable two-mode mixture of coherent states. We…

Quantum Physics · Physics 2012-08-13 Lars S. Madsen , Adriano Berni , Mikael Lassen , Ulrik L. Andersen

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

In recent years the paradigm based on entanglement as the unique measure of quantum correlations has been challenged by the rise of new correlation concepts, such as quantum discord, able to reveal quantum correlations that are present in…

Quantum Physics · Physics 2013-05-30 Paolo Giorda , Michele Allegra , Matteo G. A. Paris

We propose a measure of non-classical correlations in bipartite quantum states based on local unitary operations. We prove the measure is non-zero if and only if the quantum discord is non-zero; this is achieved via a new characterization…

Quantum Physics · Physics 2013-06-25 Sevag Gharibian

This work is at the interface of graph theory and quantum mechanics. Quantum correlations epitomize the usefulness of quantum mechanics. Quantum discord is an interesting facet of bipartite quantum correlations. Earlier, it was shown that…

Quantum Physics · Physics 2019-04-08 Supriyo Dutta , Bibhas Adhikari , Subhashish Banerjee

While entanglement is a cornerstone of quantum theory and holography, quantum correlations arising from superposition, such as quantum discord, offer a broader perspective that has remained largely unexplored in holography. We construct…

High Energy Physics - Theory · Physics 2026-02-11 Takato Mori

In this article, we investigate the geometric discord of quantum states of fermionic system in accelerated frame. It is shown by the method beyond the single-mode approximation, depending on the region considered, that the geometric discord…

Quantum Physics · Physics 2012-10-12 Jinho Chang , L. C. Kwek , Younghun Kwon

In this paper, we study global quantum discord (GQD) in infinite-size spin chains. For this purpose, in the framework of matrix product states (MPSs), we propose an effective procedure to calculate GQD (denoted as Gn) for consecutive n-site…

Quantum correlation is a key to our understanding of quantum physics. In particular, it is essential for the powerful applications to quantum information and quantum computation. There exist quantum correlations beyond entanglement, such as…

Quantum Physics · Physics 2012-03-20 Yu Guo , Jinchuan Hou

Composite quantum systems can be in generic states characterized not only by entanglement, but also by more general quantum correlations. The interplay between these two signatures of nonclassicality is still not completely understood. In…

Quantum Physics · Physics 2011-11-17 Davide Girolami , Gerardo Adesso

We investigate the dynamics of quantum discord and entanglement for a class of mixed qubit-qutrit states assuming that only the qutrit is under the action of a dephasing channel. We demonstrate that even though the entanglement in the…

Quantum Physics · Physics 2013-04-02 G. Karpat , Z. Gedik