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Related papers: Oblique discord

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Nonclassical correlations beyond entanglement might provide a resource in quantum information tasks, such as quantum computation or quantum metrology. Quantum discord is a measure of nonclassical correlations, to which entanglement belongs…

Quantum Physics · Physics 2019-05-16 Akira Sone , Quntao Zhuang , Changhao Li , Yi-Xiang Liu , Paola Cappellaro

Recently, the fast development of quantum technologies led to the need for tools allowing the characterization of quantum resources. In particular, the ability to estimate non-classical aspects, e.g. entanglement and quantum discord, in…

We perform an experimental investigation of Quantum Discord with Spin-Orbit X-states. These states are prepared through the incoherent superposition of different laser beans, where a two-level system is encoded in polarization and the…

Quantum Physics · Physics 2023-12-29 V. S. Lamego , D. G. Braga , W. F. Balthazar , J. A. O. Huguenin

We study the scaling of quantum discord (a measure of quantum correlation beyond entanglement) in spin models analytically and systematically. We find that at finite temperature the block scaling of quantum discord satisfies an area law for…

Quantum Physics · Physics 2014-02-13 Yichen Huang

Quantum discord is a form of correlation that is defined as the difference between quantum and classical mutual information of two parties. Due to the optimization involved in the definition of classical mutual information of quantum…

Quantum Physics · Physics 2024-01-23 Narjes Taghadomi , Azam Mani , Ali Fahim , Ali Bakoui , Mohammad Sadegh Salami

Two classically identical expressions for the mutual information generally differ when the two systems involved are quantum. We investigate this difference -- quantum discord -- and show that it can be used as a criterion for the…

Quantum Physics · Physics 2013-05-29 Harold Ollivier , Wojciech H. Zurek

We study the procedure for sequential unambiguous state discrimination. A qubit is prepared in one of two possible states, and measured by two observers Bob and Charlie sequentially. A necessary condition for the state to be unambiguously…

Quantum Physics · Physics 2013-12-02 Chao-Qian Pang , Fu-Lin Zhang , Li-Fang Xu , Mai-Lin Liang , Jing-Ling Chen

We find that when a qubit initialized in a pure state experiences pure dephasing due to interaction with an environment, separable qubit-environment states generated during the evolution also have zero quantum discord with respect to the…

Quantum Physics · Physics 2018-01-17 Katarzyna Roszak , Łukasz Cywiński

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

Recent results in quantum information theory characterize quantum coherence in the context of resource theories. Here we study the relation between quantum coherence and quantum discord, a kind of quantum correlation which appears even in…

Quantum Physics · Physics 2016-04-29 Jiajun Ma , Benjamin Yadin , Davide Girolami , Vlatko Vedral , Mile Gu

We relate the problem of irreversibility of entanglement with the recently defined measures of quantum correlation - quantum discord and one-way quantum deficit. We show that the entanglement of formation is always strictly larger than the…

Quantum Physics · Physics 2011-07-11 Marcio F. Cornelio , Marcos C. de Oliveira , Felipe F. Fanchini

We propose a scheme to evaluate the amount of quantum discord and entanglement of formation for mixed states, and reveal their ordering relation via an intrinsic relationship between the two quantities distributed in different partners of…

Quantum Physics · Physics 2015-05-19 Li-Xiang Cen , Xin-Qi Li , JiuShu Shao , YiJing Yan

It is known from the analysis of the density matrix for bipartite systems that the quantum discord (as a measure of quantum correlations) depends on the particular subsystem chosen for the projective measurements. We study asymmetry of the…

Quantum Physics · Physics 2015-05-27 E. B. Fel'dman , A. I. Zenchuk

Quantum chaos is the study of quantum systems whose classical description is chaotic. How does chaos manifest itself in the quantum world? In this spirit, we study the dynamical generation of entanglement as a signature of chaos in a system…

Quantum Physics · Physics 2012-12-20 Vaibhav Madhok

It is shown that the dissonance, a quantum correlation which is equal to quantum discord for separable state, is required for assisted optimal state discrimination. We find that only one side discord is required in the optimal process of…

Quantum Physics · Physics 2012-02-24 Bo Li , Shao-Ming Fei , Zhi-Xi Wang , Heng Fan

We revisit the problem of the dynamics of quantum correlations in the exact Tavis-Cummings model. We show that many of the dynamical features of quantum discord attributed to dissipation are already present in the exact framework and are…

Quantum Physics · Physics 2016-06-22 Juliana Restrepo , Boris A. Rodriguez

We present a scheme of quantum information transmission, which transmits the quantum information contained in a single qubit via the quantum correlation shared by two parties (a two-qubit channel), whose quantum discord is non-zero. We…

Quantum Physics · Physics 2012-02-22 Lei Wang , Jie-Hui Huang , Jonathan P. Dowling , Shi-Yao Zhu

Correlations may arise in quantum systems through various means, of which the most remarkable one is quantum entanglement. Additionally, there are systems that exhibit non-classical correlations even in the absence of entanglement. Quantum…

Quantum Physics · Physics 2024-08-13 Gökhan Torun

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement is explored for bi-partite and multi-partite pure and mixed states.…

Quantum Physics · Physics 2009-05-18 Tzu-Chieh Wei

The quantum discord is used as measure of quantum correlations for two families of multipartite coherent states. The first family interpolates between generalized GHZ states and generalized Werner states. The second one is an interpolation…

Quantum Physics · Physics 2012-11-01 M. Daoud , R. Ahl Laamara