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Related papers: Quantum correlations in spin models

200 papers

We develop connections between generalised notions of entanglement and quantum computational devices where the measurements available are restricted, either because they are noisy and/or because by design they are only along Pauli…

Quantum Physics · Physics 2012-01-18 N. Ratanje , S. Virmani

We investigate whether paradigmatic measurements for quantum state tomography, namely mutually unbiased bases and symmetric informationally complete measurements, can be employed to certify quantum correlations. For this purpose, we…

We study dynamics of nonclassical correlations by exactly solving a model consisting of two atomic qubits with spontaneous emission. We find that the nonclassical correlations defined by different measures give different qualitative…

Quantum Physics · Physics 2012-02-01 Ming-Liang Hu , Heng Fan

Quantum correlations forms a subset of the set of nonsignaling boxes. This allows us to characterize quantum correlations as a convex combination of the extremal boxes of the nonsignaling polytope which are Popescu-Rohrlich boxes (maximally…

Quantum Physics · Physics 2016-10-13 C. Jebaratnam

Quantification of nonclassicality and entanglement in a quantum state is crucial for quantum advantage in information processing and computation. Robustness is one of the tractable measures for quantifying quantum resources. Gaussian states…

Quantum Physics · Physics 2023-09-22 Xiao-yu Chen

Dissimilar notions of quantum correlations have been established, each being motivated through particular applications in quantum information science and each competing for being recognized as the most relevant measure of quantumness. In…

Quantum Physics · Physics 2021-05-05 S. Köhnke , E. Agudelo , M. Schünemann , O. Schlettwein , W. Vogel , J. Sperling , B. Hage

Bell nonlocality refers to correlations between two distant, entangled particles that challenge classical notions of local causality. Beyond its foundational significance, nonlocality is crucial for device-independent technologies like…

The origin of non-classical correlations is difficult to identify since the uncertainty principle requires that information obtained about one observable invariably results in the disturbance of any other non-commuting observable. Here,…

Quantum Physics · Physics 2014-07-01 Holger F. Hofmann

By applying complementary analytic and numerical methods, we investigate the dynamics of spin-$1/2$ XXZ models with variable-range interactions in arbitrary dimensions. The dynamics we consider is initiated from uncorrelated states that are…

We propose a modified metric based on the Hilbert-Schmidt norm and adopt it to define a rescaled version of the geometric measure of quantum discord. Such a measure is found not to suffer from the pathological dependence on state purity.…

Quantum Physics · Physics 2013-06-21 Tommaso Tufarelli , Tom MacLean , Davide Girolami , Ruggero Vasile , Gerardo Adesso

It is shown that a choice of degrees of freedom of a bipartite continuous variable system determines amount of non-classical correlations (quantified by discord) in the system's state. Non-classical correlations (that include entanglement…

Quantum Physics · Physics 2013-04-01 M. Dugic , M. Arsenijevic , J. Jeknic-Dugic

It has been suggested that there may exist quantum correlations that go beyond entanglement. The existence of such correlations can be revealed by quantum discord, but not by the conventional measure of entanglement. We argue that a state…

Quantum Physics · Physics 2016-09-30 Pankaj Agrawal , Sk Sazim , Indranil Chakrabarty , Arun K. Pati

Analytical expressions for the entanglement measures concurrence, i-concurrence and 3-tangle in terms of spin correlation functions are derived using general symmetries of the quantum spin system. These relations are exploited for the…

Quantum Physics · Physics 2009-11-10 Ulrich Glaser , Helmut Büttner , Holger Fehske

Open quantum systems have attracted great attention, since inevitable coupling between quantum systems and their environment greatly affects the features of interest of these systems. Quantum discord, is a measure of the total nonclassical…

Quantum Physics · Physics 2012-11-30 Jin-Shi Xu , Chuan-Feng Li

Which nonlocal correlations can be obtained, when a party has access to more than one subsystem? While traditionally nonlocality deals with spacelike separated parties, this question becomes important with quantum technologies that connect…

Quantum Physics · Physics 2023-09-04 Moisés Bermejo Morán , Alejandro Pozas-Kerstjens , Felix Huber

Taking a system of two coupled qubits described by a X-shaped state and interacting through an anisotropic Heisenberg XY interaction, we examine the evolution of quantum entanglement and a few quantum correlations beyond entanglement, local…

Quantum Physics · Physics 2024-12-03 S. V. Mousavi

With the purpose to reveal consistency between multiple quantum (MQ) coherences and entanglement, we investigate numerically the dynamics of these phenomena in one-dimensional linear chains and ring of nuclear spins 1/2 coupled by dipole…

Quantum Physics · Physics 2009-05-26 G. B. Furman , V. M. Meerovich , V. L. Sokolovsky

The unique entanglement measure is concurrence in a 2-qubit pure state. The maximum violation of Bell's inequality is monotonically increasing for this quantity. Therefore, people expect that pure state entanglement is relevant to the…

Quantum Physics · Physics 2022-12-14 Xingyu Guo , Chen-Te Ma

As an important resource to realize quantum information, quantum correlation displays different behaviors, freezing phenomenon and non-localization, which are dissimilar to the entanglement and classical correlation, respectively. In our…

Quantum Physics · Physics 2018-12-10 Qin-Sheng Zhu , Xiao-Yu Li , Ming-Zheng Zhu , Yi-Ming Huang , Hao Wu , Shao-Yi Wu

Combining recent advances in superconducting quantum hardware, we explore quantum correlations in a previously inaccessible regime by observing \emph{simultaneously} high-dimensional and many-body Bell non-locality. We report a…

Quantum Physics · Physics 2026-04-28 Yousef Mafi , Ali G. Moghaddam , Teemu Ojanen