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Related papers: Quantum channels in random spin chains

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A general entangled qubit pair is analyzed in the de Broglie-Bohm formalism corresponding to two spin-1/2 quantum rotors. Several spin-spin correlators of Bohm's hidden variables are analyzed numerically and a detailed comparison with…

Quantum Physics · Physics 2015-06-04 A. Ramsak

We investigate entanglement of spin pairs in alternating open spin chains in the equilibrium state in an external magnetic field. We calculate the reduced density matrix of spin pairs and estimate the concurrence with Wootter's criteria.…

Quantum Physics · Physics 2009-11-13 S. I. Doronin , E. B. Fel'dman , A. N. Pyrkov

We study entanglement creation between two independent XX chains, which are repeatedly coupled locally to spin-1/2 Bell pairs. We show analytically that in the steady state the entanglement of the Bell pairs is perfectly transferred to the…

Quantum Physics · Physics 2015-04-29 Pierre Wendenbaum , Thierry Platini , Dragi Karevski

We investigate the transfer of genuine multipartite entanglement across a spin-1/2 chain with nearest-neighbor XX-type interaction. We focus on the perturbative regime, where a block of spins is weakly coupled at each edge of a quantum…

Quantum Physics · Physics 2020-04-10 Tony J. G. Apollaro , Claudio Sanavio , Wayne Jordan Chetcuti , Salvatore Lorenzo

We consider the spin-1/2 XY chain in a transverse field with regularly varying exchange interactions and on-site fields. In two limiting cases of the isotropic XX and extremely anisotropic (Ising) exchange interaction the thermodynamic…

Condensed Matter · Physics 2009-11-07 Oleg Derzhko

We evaluate the exact concurrence between any two spins in a cyclic XX chain of n spins placed in a uniform transverse magnetic field, both at zero and finite temperature, by means of the Jordan-Wigner transformation plus a number parity…

Quantum Physics · Physics 2015-05-13 N. Canosa , R. Rossignoli

The growth in the demand for precisely crafted many-body systems of spin-$1/2$ particles/qubits is due to their top-notch versatility in application-oriented quantum-enhanced protocols and the fundamental tests of quantum theory. Here we…

Quantum Physics · Physics 2020-10-14 Artur Niezgoda , Miłosz Panfil , Jan Chwedeńczuk

A formula to evaluate the entanglement in an one-dimensional ferrimagnetic system is derived. Based on the formula, we find that the thermal entanglement in a small size spin-1/2 and spin-s ferrimagnetic chain is rather robust against…

Quantum Physics · Physics 2009-11-13 Xiaoguang Wang , Z. D. Wang

We demonstrate remote entanglement of trapped-ion qubits via a quantum-optical fiber link with fidelity and rate approaching those of local operations. Two ${}^{88}$Sr${}^{+}$ qubits are entangled via the polarization degree of freedom of…

We show that the expectation value of squared correlations measured along random local directions is an identifier of quantum entanglement in pure states which can be directly experimentally assessed if two copies of the state were…

Quantum Physics · Physics 2015-11-18 Minh Cong Tran , Borivoje Dakic , Francois Arnault , Wieslaw Laskowski , Tomasz Paterek

The quantum entanglement measure is determined, for the first time, for antiferromagnetic trimer spin-1/2 Heisenberg chains. The physical quantity proposed to measure the entanglement is the distance between states by adopting the…

Quantum Physics · Physics 2015-04-14 O. M. Del Cima , D. H. T. Franco , S. L. L. da Silva

We show that two identical solid-state qubits can be made fully entangled (starting from completely mixed state) with probability 1/4 just measuring them by a detector, equally coupled to the qubits. This happens in the case of repeated…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Rusko Ruskov , Alexander N. Korotkov

Quasi-one-dimensional quantum antiferromagnets formed by a d-dimensional hypercubic lattice of weakly coupled spin-1/2 antiferromagnetic Heisenberg chains are studied by combining exact results in one-dimension and renormalization group…

Strongly Correlated Electrons · Physics 2009-10-28 Ziqiang Wang

Quantum entanglement between distant qubits is an important feature of quantum networks. Distribution of entanglement over long distances can be enabled through coherently interfacing qubit pairs via photonic channels. Here, we report the…

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

In this contribution we consider an advantageous building block with potential for various quantum applications: a device based on coupled spins capable of generating and sharing out an entangled pair of qubits. Our model device is a…

Quantum Physics · Physics 2020-11-13 M. P. Estarellas , T. P. Spiller , I. D'Amico

A scheme for generating an entangled state in a two spin-1/2 system by means of a spin-dependent potential scattering of another qubit is presented and analyzed in three dimensions. The entanglement is evaluated in terms of the concurrence…

Quantum Physics · Physics 2010-04-07 Yuichiro Hida , Hiromichi Nakazato , Kazuya Yuasa , Yasser Omar

We give an elementary introduction to the notion of quantum entanglement between distinguishable parties and review a recent proposal about solid state quantum computation with spin-qubits in quantum dots. The indistinguishable character of…

Condensed Matter · Physics 2007-05-23 John Schliemann , Daniel Loss

We compute the quantum correlation (quantum discord (QD)) and the entanglement (EoF) between nearest neighbor qubits (spin-1/2) in an infinite chain described by the Heisenberg model (XXZ Hamiltonian) at finite temperatures. The chain is in…

Quantum Physics · Physics 2015-05-19 T. Werlang , C. Trippe , G. A. P. Ribeiro , Gustavo Rigolin

One-dimensional spin-1/2 systems are well-known candidates to study the quantum correlations between particles. In the condensed matter physics, studies often are restricted to the 1st neighbor particles. In this work, we consider the 1D…

Strongly Correlated Electrons · Physics 2017-11-08 Salimeh Mahdavifar , Saeed Mahdavifar , R. Jafari