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Related papers: Concurrence in Disordered Systems

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We study the correlation dynamics of a system composed of arbitrary numbers of qutrits interacting with a common environment. Initially, the system is assumed to be in a low dimensional subspace of the Hamiltonian called "decoherence-free…

Quantum Physics · Physics 2017-06-15 R. Sufiani , A. Pedram , M. Karimi

The distribution of entanglement of typical multiparty quantum states is not uniform over the range of the measure utilized for quantifying the entanglement. We intend to find the response to disorder in the state parameters on this…

Quantum Physics · Physics 2022-12-29 George Biswas , Anindya Biswas , Ujjwal Sen

Quantum information theory and quantum computing are theoritical basis of quantum computers. Thanks to entanglement, quantum mechanical systems are provisioned to realize many information processing problems faster than classical…

Quantum Physics · Physics 2017-04-19 Volkan Erol

We study the concurrence of arbitrary dimensional bipartite quantum systems. By using a positive but not completely positive map, we present an analytical lower bound of concurrence. Detailed examples are used to show that our bound can…

Quantum Physics · Physics 2014-01-09 Hui-hui Qin , Shao-Ming Fei

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

We study the signatures of disorder in the production of orbital electron entanglement in quantum wires. Disordered entanglers suffer the effects of localization of the electron wave function and random fluctuations in the entanglement…

Mesoscale and Nanoscale Physics · Physics 2014-03-07 Alberto Aleta , Héctor Villarubia-Rojo , Diego Frustaglia , Víctor A. Gopar

We analyze the interplay of chaos, entanglement and decoherence in a system of qubits whose collective behaviour is that of a quantum kicked top. The dynamical entanglement between a single qubit and the rest can be calculated from the mean…

Quantum Physics · Physics 2009-11-13 S. Ghose , R. Stock , P. S. Jessen , R. Lal , A. Silberfarb

For a given pure state of multipartite system, the concurrence vector is defined by employing the defining representation of generators of the corresponding rotation groups. The norm of concurrence vector is considered as a measure of…

Quantum Physics · Physics 2009-11-10 S. J. Akhtarshenas

The entanglement in a general mixed spin chain with arbitrary spin $S$ and 1/2 is investigated in the thermodynamical limit. The entanglement is witnessed by the magnetic susceptibility which decides a characteristic temperature for an…

Quantum Physics · Physics 2009-11-13 Xiang Hao , Shiqun Zhu

Entanglement and quantum discord for a pair of nuclear spins $s=1/2$ in a nanopore filled with a gas of spin-carrying molecules (atoms) are studied. The correlation functions describing dynamics of dipolar coupled spins in a nanopore are…

Quantum Physics · Physics 2012-11-12 E. B. Fel'dman , E. I. Kuznetsova , M. A. Yurishchev

In the framework of the theory of open systems, we give a description of quantum entanglement and quantum discord for two non-interacting modes embedded in a thermal environment. We describe the evolution of entanglement in terms of the…

Quantum Physics · Physics 2015-06-12 Aurelian Isar

We investigate the non-equilibrium thermal quantum discord and entanglement of a three-spin chain whose two end spins are respectively coupled to two thermal reservoirs at different temperatures. In the three-spin chain, besides the XX-type…

Quantum Physics · Physics 2015-05-28 Xiu-xing Zhang , Fu-li Li

We discuss a generalization of the conditional entropy and one-way information deficit in quantum systems, based on general entropic forms. The formalism allows to consider simple entropic forms for which a closed evaluation of the…

Quantum Physics · Physics 2017-12-29 N. Canosa , M. Cerezo , N. Gigena , R. Rossignoli

Disorder has been long considered as a formidable foe of theoretical physicists in their attempts to understand system's behavior. Here, we review recently accumulated data and propose that from the point of view of calculating…

Soft Condensed Matter · Physics 2014-08-28 V. V. Brazhkin , K. Trachenko

Quantum many-body systems are commonly considered as quantum chaotic if their spectral statistics, such as the level spacing distribution, agree with those of random matrix theory. Using the example of the kicked Ising chain we demonstrate…

Quantum Physics · Physics 2023-10-16 Tabea Herrmann , Maximilian F. I. Kieler , Arnd Bäcker

The parameterized entanglement monotone, the $q$-concurrence, is also a reasonable parameterized entanglement measure. By exploring the properties of the $q$-concurrence with respect to the positive partial transposition and realignment of…

Quantum Physics · Physics 2022-06-17 Zhi-Wei Wei , Ming-Xing Luo , Shao-Ming Fei

We study the concurrence of four-qubit quantum states and provide analytical lower bounds of concurrence in terms of the monogamy inequality of concurrence for qubit systems. It is shown that these lower bounds are able to improve the…

Quantum Physics · Physics 2014-02-11 Xue-Na Zhu , Shao-Ming Fei

The competition between evolution time, interaction strength, and temperature challenges our understanding of many-body quantum systems out-of-equilibrium. Here we consider a benchmark system, the Hubbard dimer, which allows us to explore…

Quantum Physics · Physics 2018-11-14 Marcela Herrera , Krissia Zawadzki , Irene D'Amico

How violently do two quantum operators disagree? Different fields of physics feature different measures of incompatibility: (i) In quantum information theory, entropic uncertainty relations constrain measurement outcomes. (ii) In condensed…

Quantum Physics · Physics 2019-08-13 Nicole Yunger Halpern , Anthony Bartolotta , Jason Pollack

While the detection of entanglement has been proved already to be quite a difficult task, experimental quantification of entanglement is even more challenging. In this work, we derive an analytical lower bound for the concurrence of a…

Quantum Physics · Physics 2011-04-07 Zhi-Hao Ma , Zhi-Hua Chen , Jing-Ling Chen