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Related papers: Discord and quantum computational resources

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Quantum discord was proposed as an information theoretic measure of the ``quantumness'' of correlations. I show that discord determines the difference between the efficiency of quantum and classical Maxwell's demons in extracting work from…

Quantum Physics · Physics 2007-05-23 Wojciech Hubert Zurek

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 refers to an important aspect of quantum correlations for bipartite quantum systems. In our earlier works we have shown that corresponding to every graph (combinatorial) there are quantum states whose properties are…

Quantum Physics · Physics 2019-03-20 Supriyo Dutta , Bibhas Adhikari , Subhashish Banerjee

Quantum coherence is a prime resource in quantum computing and quantum communication. Quantum coherence of an arbitrary qubit state can be created at a remote location using maximally entangled state, local operation and classical…

Quantum Physics · Physics 2023-02-09 Jasleen Kaur , Shrobona Bagchi , Arun Kumar Pati

Control at the interface between the classical and the quantum world is fundamental in quantum physics. In particular, how classical control is enhanced by coherence effects is an important question both from a theoretical as well as from a…

Quantum Physics · Physics 2016-08-17 J. M. Matera , D. Egloff , N. Killoran , M. B. Plenio

Quantum discord is a prominent measure of quantum correlations, playing an important role in expanding its horizon beyond entanglement. Here we provide an operational meaning of (geometric) discord, which quantifies the amount of…

Quantum Physics · Physics 2015-06-05 Satyabrata Adhikari , Subhashish Banerjee

Quantum state discrimination plays a central role in defining the possible and impossible operations through a restricted class of quantum operations. A seminal result by Bennett et al. [Phys. Rev. A 59, 1070 (1999)] demonstrates the…

Quantum Physics · Physics 2025-10-01 Hyukjoon Kwon

The quantum correlations, including entanglement and discord with its geometric measure, and classical correlation are studied for a bipartite partition of a open or closed quantum system. It is found that the purity of the initial state…

Quantum Physics · Physics 2013-01-31 Abdel-Baset A. Mohamed

Quantum systems in mixed states can be unentangled and yet still correlated in a way that is not possible for classical systems. These correlations can be quantified by the quantum discord and might provide a resource for certain…

Quantum Physics · Physics 2014-05-26 B. P. Lanyon , P. Jurcevic , C. Hempel , M. Gessner , V. Vedral , R. Blatt , C. F. Roos

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

Discord, originally notable as a signature of bipartite quantum correlation,in fact can be nonzero classically, i.e., arising from noisy measurements by one of the two parties. Here we redefine classical discord to quantify channel…

Quantum Physics · Physics 2021-09-16 Wei-Wei Zhang , Yuval R. Sanders , Barry C. Sanders

Quantum discord is an important measure of quantum correlations that can serve as a resource for certain types of quantum information processing. \ Like entanglement, discord is subject to destruction by external noise. The routes by which…

Quantum Physics · Physics 2013-10-22 Nga T. T. Nguyen , Robert Joynt

Quantum discord, and a number of related indicators, are currently raising a relentless interest as a novel paradigm of non-classical correlations beyond entanglement. Beside merely fundamental aspects, various works have shown that discord…

Quantum Physics · Physics 2014-02-27 Alessandro Farace , Francesco Ciccarello , Rosario Fazio , Vittorio Giovannetti

The concept of quantum discord aims at unveiling quantum correlations that go beyond those described by entanglement. Its original formulation [J. Phys. A 34, 6899 (2001); Phys. Rev. Lett 88, 017901 (2002)] is difficult to compute even for…

Understanding the role that quantum entanglement plays as a resource in various information processing tasks is one of the crucial goals of quantum information theory. Here we propose a new perspective for studying quantum entanglement:…

Quantum Physics · Physics 2015-09-23 L. Czekaj , M. Pawlowski , T. Vertesi , A. Grudka , M. Horodecki , R. Horodecki

Quantum Discord (QD) is a measure of the total quantum non-local correlations of a quantum system. The formalism of quantum discord has been applied to various two-qubit mixed states and it has been reported that there is a non-zero quantum…

Quantum Physics · Physics 2022-10-04 M. S. Ramkarthik , Devvrat Tiwari , Pranay Barkataki

We argue that the dimensionality of the space of quantum systems' states should be considered as a legitimate resource for quantum information tasks. The assertion is supported by the fact that quantum states with discord-like capacities…

Quantum Physics · Physics 2016-01-19 Angelo Plastino , Guido Bellomo , Angel R. Plastino

We evaluate the quantum discord dynamics of two qubits in independent and common non-Markovian environments. We compare the dynamics of entanglement with that of quantum discord. For independent reservoirs the quantum discord vanishes only…

Quantum Physics · Physics 2015-03-13 F. F. Fanchini , T. Werlang , C. A. Brasil , L. G. E. Arruda , A. O. Caldeira

Using the methods of quantum trajectories we investigate the effects of dissipative decoherence in a quantum computer algorithm simulating dynamics in various regimes of quantum chaos including dynamical localization, quantum ergodic regime…

Quantum Physics · Physics 2016-09-08 Jae Weon Lee , Dima L. Shepelyansky

In this paper, we consider quantum correlations (quantum discord and local quantum uncertainty) in a vertical quantum dot. Their dependencies on magnetic field and temperature are presented in detail. It is noticeable that, quantum discord…

Quantum Physics · Physics 2014-01-21 E. Faizi , H. Eftekhari