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Related papers: Entanglement and Concurrence in the BCS State

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In this paper, we study the bipartite entanglement of spin coherent states in the case of pure and mixed states. By a proper choice of the subsystem spins, the entanglement for large class of quantum systems is investigated. We generalize…

Quantum Physics · Physics 2015-06-12 K. Berrada , A. Mohammadzade , S. Abdel-Khalek , H. Eleuch , S. Salimi

We discuss a kind of generalized concurrence for a class of high dimensional quantum pure states such that the entanglement of formation is a monotonically increasing convex function of the generalized concurrence. An analytical expression…

Quantum Physics · Physics 2009-11-10 Shao-Ming Fei , Zhi-Xi Wang , Hui Zhao

We revisit the quantization of the order parameter, which we refer to as third quantization, from the perspective of the commutation relation between the phase operator of the order parameter and the particle-number operator. We show that…

Quantum Physics · Physics 2026-04-24 Guo-Jian Qiao , Miao-Miao Yi , Xin Yue , C. P. Sun

Entanglement concurrence has been widely used for featuring entanglement in quantum experiments. As an entanglement monotone it is related to specific quantum Tsallis entropy. Our goal in this paper is to propose a new parameterized…

Quantum Physics · Physics 2021-05-26 Xue Yang , Ming-Xing Luo , Yan-Han Yang , Shao-Ming Fei

Recently in Ref.\cite{Wen:2021qgx}, one of the authors introduced the balanced partial entanglement (BPE), which has been proposed to be dual to the entanglement wedge cross-section (EWCS). In this paper, we explicitly demonstrate that the…

High Energy Physics - Theory · Physics 2022-04-22 Hugo A. Camargo , Pratik Nandy , Qiang Wen , Haocheng Zhong

The Schmidt coefficients capture all entanglement properties of a pure bipartite state and therefore determine its usefulness for quantum information processing. While the quantification of the corresponding properties in mixed states is…

Quantum Physics · Physics 2019-04-08 Gael Sentís , Christopher Eltschka , Otfried Gühne , Marcus Huber , Jens Siewert

This work is an enquiry into the circumstances under which entropy methods can give an answer to the questions of both quantum separability and classical correlations of a composite state. Several entropy functionals are employed to examine…

Quantum Physics · Physics 2009-11-07 A. K. Rajagopal , R. W. Rendell

We derive an analytical lower bound for the concurrence of a bipartite quantum state in arbitrary dimension. A functional relation is established relating concurrence, the Peres-Horodecki criterion and the realignment criterion. We…

Quantum Physics · Physics 2007-05-23 Kai Chen , Sergio Albeverio , Shao-Ming Fei

A simplified expression of concurrence for two-qubit mixed state having no more than three non-vanishing eigenvalues is obtained. Basing on SU(2) coherent states, the amount of entanglement of two-qubit pure states is studied and conditions…

Quantum Physics · Physics 2012-04-06 S. Salimi , A. Mohammadzade , K. Berrada

We propose and examine several candidates for universal multipartite entanglement measures. The most promising candidate for applications needing entanglement in the full Hilbert space is the ent-concurrence, which detects all entanglement…

Quantum Physics · Physics 2018-04-19 Samuel R. Hedemann

We develop an original approach for the quantitative characterisation of the entanglement properties of, possibly mixed, bi- and multipartite quantum states of arbitrary finite dimension. Particular emphasis is given to the derivation of…

Quantum Physics · Physics 2009-11-11 Florian Mintert , Andre R. R. Carvalho , Marek Kus , Andreas Buchleitner

In contrast to abstract statistical analyses in the literature, we present a concrete physical diagrammatic model of entanglement characterization and measure with its underlying discrete phase-space physics. This paper serves as a…

Quantum Physics · Physics 2023-05-30 Felix A. Buot

A "super-atom" conceptual interface between chemistry and physics is proposed in order to assist in the search for higher TC superconductors. High-TC superconductivity HTSC is articulated as the entanglement of two disjoint electronic…

Superconductivity · Physics 2015-06-03 Itai Panas

Monogamy of entanglement is generally discussed using a bipartite entanglement measure as an upper bound. Here we discuss a new kind of monogamous relation where the upper bound is given by a multipartite measure of entanglement, the…

Quantum Physics · Physics 2013-03-27 Marcio F. Cornelio

We formulate an entanglement criterion using Peres-Horodecki positive partial transpose operations combined with the Schr\"odinger-Robertson uncertainty relation. We show that any pure entangled bipartite and tripartite state can be…

Quantum Physics · Physics 2009-11-13 J. Gillet , T. Bastin , G. S. Agarwal

In the physics of flavor mixing, the flavor states are given by superpositions of mass eigenstates. By using the occupation number to define a multiqubit space, the flavor states can be interpreted as multipartite mode-entangled states. By…

Quantum Physics · Physics 2009-07-02 M. Blasone , F. Dell'Anno , S. De Siena , M. Di Mauro , F. Illuminati

We qualify the entanglement of arbitrary mixed states of bipartite quantum systems by comparing global and marginal mixednesses quantified by different entropic measures. For systems of two qubits we discriminate the class of maximally…

Quantum Physics · Physics 2007-05-23 Gerardo Adesso , Fabrizio Illuminati , Silvio De Siena

We define the concurrence hierarchy as d-1 independent invariants under local unitary transformations in d-level quantum system. The first one is the original concurrence defined by Wootters et al in 2-level quantum system and generalized…

Quantum Physics · Physics 2009-11-07 Heng Fan , Keiji Matsumoto , Hiroshi Imai

The relative entropy of entanglement is defined in terms of the relative entropy between an entangled state and its closest separable state (CSS). Given a multipartite-state on the boundary of the set of separable states, we find a closed…

Quantum Physics · Physics 2011-06-03 Shmuel Friedland , Gilad Gour

Entanglement potentials are a promising way to quantify the nonclassicality of single-mode states. They are defined by the amount of entanglement (expressed by, e.g., the Wootters concurrence) obtained after mixing the examined single-mode…

Quantum Physics · Physics 2024-01-12 Josef Kadlec , Karol Bartkiewicz , Antonín Černoch , Karel Lemr , Adam Miranowicz