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Related papers: Quantum discord for two-qubit X-states

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Xu [Jianwei Xu, J. Phys. A: Math. Theor. 45 405304 (2012)] generalized geometric quantum discord [B.Dakic, V. Vedral, and C . Brukner, Phys. Rev. Lett. 105 190502 (2010)] to multipartite states and proposed the geometric global quantum…

Quantum Physics · Physics 2016-03-23 Wen-Chao Qiang , Hua-Ping Zhanga , Lei Zhang

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

It is known that a reliable geometric quantifier of discord-like correlations can be built by employing the so-called trace distance. This is used to measure how far the state under investigation is from the closest "classical-quantum" one.…

Quantum Physics · Physics 2014-01-24 F. Ciccarello , T. Tufarelli , V. Giovannetti

We utilize quantum discord to charecterize the correlation present in Buzek-Hillery quantum copying machine \cite{bh} (not necessarily universal quantum cloning machine). In other words we quantify the correlation present beetween the…

Quantum Physics · Physics 2010-07-14 Indranil Chakrabarty

We build a machine learning model to detect correlations in a three-qubit system using a neural network trained in an unsupervised manner on randomly generated states. The network is forced to recognize separable states, and correlated…

Quantum Physics · Physics 2024-08-20 Mateusz Krawczyk , Jarosław Pawłowski , Maciej M. Maśka , Katarzyna Roszak

We investigate the phenomenon of sudden transition between classical and quantum decoherence in the study of quantum discord for a dissipative cavity QED system, which consists of two noninteracting two-level atoms, each trapped in a…

Quantum Physics · Physics 2015-03-19 Qi-Liang He , Jing-Bo Xu , Dao-Xin Yao , Ye-Qi Zhang

We investigate the distribution property of one way discord in multipartite system by introducing the concept of polygamy deficit for one way discord. The difference between one way discord and quantum discord is analogue to the difference…

Quantum Physics · Physics 2016-08-18 Si-Yuan Liu , Yu-Ran Zhang , Wen-Li Yang , Heng Fan

The last two decades have witnessed a rapid development of quantum information processing, a new paradigm which studies the power and limit of "quantum advantages" in various information processing tasks. Problems such as when quantum…

Quantum Physics · Physics 2015-02-03 Zhaohui Wei , Shengyu Zhang

Quantum correlations in multiple quantum (MQ) NMR experiments are investigated in two-spin systems (dimers). In the initial moment of time one spin is in a pure quantum polarized state and the other spin is in the thermodynamic equilibrium…

Quantum Physics · Physics 2017-01-16 S. A. Gerasev , E. I. Kuznetsova

"Quantum conversation" is a way in which two parties can communicate classical information with each other using entanglement as a shared resource. We present this scheme using a multipartite entangled state after describing its generation…

Quantum Physics · Physics 2015-05-13 Sakshi Jain , Sreraman Muralidharan , Prasanta K. Panigrahi

Based on the relative entropy, we give a unified characterization of quantum correlations for nonlocality, steerability, discord and entanglement for any bipartite quantum states. For two-qubit states we show that the quantities obtained…

Quantum Physics · Physics 2017-04-14 Tinggui Zhang , Hong Yang , Xianqing Li-Jost , Shao-Ming Fei

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

Quantum discord Q is a function of density matrix elements. The domain of such a function in the case of two-qubit system with X density matrix may consist of three subdomains at most: two ones where the quantum discord is expressed in…

Quantum Physics · Physics 2015-11-11 M. A. Yurischev

We review recent studies on the measures of zero temperature quantum correlations namely, the quantum entanglement (concurrence) and discord present in the final state of a transverse XY spin chain following a quench through quantum…

Quantum Physics · Physics 2015-06-05 Tanay Nag , Amit Dutta , Ayoti Patra

We address the question of the role of quantum correlations beyond entanglement in context of quantum magnetometry. To this end, we study the evolution of the quantum discord, measured by the rescaled discord, of two electron-spin qubits…

Quantum Physics · Physics 2015-06-12 Paweł Mazurek , Katarzyna Roszak , Paweł Horodecki

Entanglement is one of the pillars of quantum mechanics and quantum information processing, and as a result the quantumness of nonentangled states has typically been overlooked and unrecognized. We give a robust definition for the…

Quantum Physics · Physics 2007-05-23 Berry Groisman , Dan Kenigsberg , Tal Mor

We study the quantum discord (QD) and the classical correlations (CC) in a reference model for strongly correlated electrons, the one-dimensional bond-charge extended Hubbard model. We show that the comparison of QD and CC and of their…

Quantum Physics · Physics 2013-05-29 Michele Allegra , Paolo Giorda , Arianna Montorsi

We consider the quantum discord in a two-particle spin-1/2 system (dimer) governed by the standard multiple quantum (MQ) Hamiltonian and reveal the relation between the discord and the intensity of the second-order MQ coherence. Since the…

Quantum Physics · Physics 2015-05-30 E. I. Kuznetsova , A. I. Zenchuk

In this work, we compute quantum discord between two causally independent areas in $3+1$ dimensions global de Sitter Axiverse to investigate the signs of quantum entanglement. For this goal, we study a bipartite quantum field theoretic…

High Energy Physics - Theory · Physics 2026-01-01 Sayantan Choudhury

Quantum discord, as a measure of all quantum correlations, has been proposed as the key resource in certain quantum communication tasks and quantum computational models without containing much entanglement. Daki\'{c}, Vedral, and Brukner…

Quantum Physics · Physics 2013-02-05 Hai-Rui Wei , Bao-Cang Ren , Fu-Guo Deng
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