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Related papers: Maximal entanglement from quantum random walks

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We study the Bell nonlocality of high dimensional quantum systems based on quantum entanglement. A quantitative relationship between the maximal expectation value B of Bell operators and the quantum entanglement concurrence C is obtained…

Quantum Physics · Physics 2021-09-01 Tinggui Zhang , Ya Xi , Shao-Ming Fei

We consider a set of fully connected spins models that display first- or second-order transitions and for which we compute the ground-state entanglement in the thermodynamical limit. We analyze several entanglement measures (concurrence,…

Statistical Mechanics · Physics 2011-03-01 M. Filippone , S. Dusuel , J. Vidal

Entanglement can be generated by two electrons in a spin-zero state on a semiconducting single-walled carbon nanotube. The two electrons, one weakly bound in a shallow well in the conduction band, and the other injected into the conduction…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 D. Gunlycke , J. H. Jefferson , T. Rejec , A. Ramsak , D. G. Pettifor , G. A. D. Briggs

We present a novel scheme to generate entanglement between two spatially separated systems. The scheme makes use of spatial entanglement generated by a single-particle quantum walk which is used to entangle two spatially separated, not…

Quantum Physics · Physics 2012-06-25 C. M. Chandrashekar , Sandeep K. Goyal , Subhashish Banerjee

Entanglement with single-particle states is advantageous in quantum technology because of their ability to encode and process information more securely than their multi-particle analogs. Threeway and nonlocal two-way entangled…

Quantum Physics · Physics 2025-01-14 Dinesh Kumar Panda , Colin Benjamin

A recently proposed history formalism is used to define temporal entanglement in quantum systems, and compute its entropy. The procedure is based on the time-reduction of the history density operator, and allows a symmetrical treatment of…

Quantum Physics · Physics 2022-04-05 Leonardo Castellani

The entanglement dynamics of spin chains is investigated using Heisenberg-XY spin Hamiltonian dynamics. The various measures of two-qubit entanglement are calculated analytically in the time-evolved state starting from initial states with…

Quantum Physics · Physics 2009-11-10 V. Subrahmanyam , Arul Lakshminarayan

Entanglement is a physical resource of a quantum system just like mass, charge or energy. Moreover it is an essential tool for many purposes of nowadays quantum information processing, e.g. quantum teleportation, quantum cryptography or…

Disordered Systems and Neural Networks · Physics 2008-02-15 Imre Varga , Jose Antonio Mendez-Bermudez

We investigate the entanglement properties of multi-mode Gaussian states, which have some symmetry with respect to the ordering of the modes. We show how the symmetry constraints the entanglement between two modes of the system. In…

Quantum Physics · Physics 2009-11-10 M. M. Wolf , F. Verstraete , J. I. Cirac

The geometric measure of entanglement of a pure quantum state is defined to be its distance to the space of product (seperable) states. Given an $n$-partite system composed of subsystems of dimensions $d_1,\ldots, d_n$, an upper bound for…

Quantum Physics · Physics 2018-05-09 Liqun Qi , Guofeng Zhang , Guyan Ni

The entanglement measure for multiqudits is proposed. This measure calculates the partial entanglement distributed by subsystems and the complete entanglement of the total system. This shows that we need to measure the subsystem…

Quantum Physics · Physics 2007-05-23 Hyuk-jae Lee , Sung Dahm Oh , Doyeol Ahn

Quantum entanglement cannot be unlimitedly shared among arbitrary number of qubits. Larger the number of entangled pairs in an N-qubit system, smaller the degree of bi-partite entanglement is. We analyze a system of N qubits in which an…

Quantum Physics · Physics 2009-11-06 Masato Koashi , Vladimir Buzek , Nobuyuki Imoto

We consider a quantum many-body system made of $N$ interacting $S{=}1/2$ spins on a lattice, and develop a formalism which allows to extract, out of conventional magnetic observables, the quantum probabilities for any selected spin pair to…

Statistical Mechanics · Physics 2007-05-23 Andrea Fubini , Tommaso Roscilde , Valerio Tognetti , Matteo Tusa , Paola Verrucchi

A general and an arbitrarily efficient scheme for entangling the spins (or any spin-like degree of freedom) of two independent uncorrelated identical particles by a combination of two particle interferometry and which way detection is…

Quantum Physics · Physics 2009-11-07 S. Bose , D. Home

We determine a general upper bound for the steady-state entanglement achievable by continuous feedback for systems of any number of bosonic degrees of freedom. We apply such a bound to the specific case of parametric interactions - the most…

Quantum Physics · Physics 2010-06-04 Alessio Serafini , Stefano Mancini

A weakly bound electron in a semiconductor quantum wire is shown to become entangled with an itinerant electron via the coulomb interaction. The degree of entanglement and its variation with energy of the injected electron, may be tuned by…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 J. H. Jefferson , A. Ramsak , T. Rejec

The frame of classical probability theory can be generalized by enlarging the usual family of random variables in order to encompass nondeterministic ones: this leads to a frame in which two kinds of correlations emerge: the classical…

Quantum Physics · Physics 2007-05-23 E. G. Beltrametti , S. Bugajski

We identify a fundamental phenomenon of heterogeneous one dimensional random walks: the escape (traversal) time is maximized when the heterogeneity in transition probabilities forms a pyramid-like potential barrier. This barrier corresponds…

Probability · Mathematics 2020-07-29 Asaf Cassel , Shie Mannor , Guy Tennenholtz

One can view quantum mechanics as a generalization of classical probability theory that provides for pairwise interference among alternatives. Adopting this perspective, we ``quantize'' the classical random walk by finding, subject to a…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Xavier Martin , Denjoe O'Connor , R. D. Sorkin

We relate the entropy of entanglement of ensembles of random vectors to their generalized fractal dimensions. Expanding the von Neumann entropy around its maximum we show that the first order only depends on the participation ratio, while…

Quantum Physics · Physics 2009-03-12 Olivier Giraud , John Martin , Bertrand Georgeot