arXiv 0705.44132007-05-30cond-mat.mes-hallcond-mat.str-elquant-ph

Entanglement in the 1D extended anisotropic Heisenberg model

E. Plekhanov, A. Avella, F. Mancini

备注：: 2 pages, 3 figures, presented at SCES'07 Houston, May 2007
发表信息：: Physica B 403, 1282 (2008)
DOI：: 10.1016/j.physb.2007.10.127

英文摘要：

We present a study of entanglement in the case of the 1D extended anisotropic Heisenberg model. We investigate two quantum phase transitions (QPTs) within the previously found ergodicity phase diagram [E. Plekhanov, A. Avella, and F. Mancini Phys. Rev. B \textbf{74}, 115120 (2006)]. Our calculations are done by means of the numerically exact Lanczos method at T=0, followed by a finite-size scaling. As a measure of entanglement we use the concurrence for two spins out of the system. We conclude from our studies that these QPTs are accompanied by a qualitative entanglement change.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

阅读原文

阅读 PDF ↗

arXiv 页面 ↗HTML 原文 ↗

本文内容

英文摘要相关论文

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

继续探索

相关论文

Frustration-driven QPT in the 1D extended anisotropic Heisenberg model

By using Density Matrix Renormalization Group (DMRG) technique we study the 1D extended anisotropic Heisenberg model. We find that starting from the ferromagnetic phase, the system undergoes two quantum phase transitions (QPTs) induced by frustration. By increasing the next-nearest-neighbor (NNN) interaction, the ground state of the system changes smoothly from a completely polarized state to a NNN correlated one. On the contrary, letting the in-plane interaction to be greater than the out-of-plane one, the ground state changes abruptly.

2007-05-30cond-mat.mes-hallcond-mat.str-elquant-ph

Ultrafast dynamics of entanglement in Heisenberg antiferromagnets

We investigate entanglement dynamics in the antiferromagnetic Heisenberg model in two dimensions following a spatially anisotropic quench of the exchange interactions. Opposed to established results in one dimension, the magnon quasiparticles show an initial growth of entanglement dynamics that does not depend on the system size and is governed by the oscillation period of the exchange interaction. We ascribe this to the dominance of the intrinsic entanglement of short wavelength non-propagating magnon-pairs, which also leads to a competition between area-law and volume-law contribution in the…

2022-03-15cond-mat.mes-hallcond-mat.str-el

Thermal and ground-state entanglement in Heisenberg XX qubit rings

We study the entanglement of thermal and ground states in Heisernberg $XX$ qubit rings with a magnetic field. A general result is found that for even-number rings pairwise entanglement between nearest-neighbor qubits is independent on both the sign of exchange interaction constants and the sign of magnetic fields. As an example we study the entanglement in the four-qubit model and find that the ground state of this model without magnetic fields is shown to be a four-body maximally entangled state measured by the $N$-tangle.

2002-05-26cond-mat.mes-hallquant-ph

Quantum entanglement and Bell inequalities in Heisenberg spin chains

We show that in one-dimensional isotropic Heisenberg model two-qubit thermal entanglement and maximal violation of Bell inequalities are directly related with a thermodynamical state function, i.e., the internal energy. Therefore they are completely determined by the partition function, the central object of thermodynamics. For ferromagnetic ring we prove that there is no thermal entanglement at any temperature. Explicit relations between the concurrence and the measure of maximal Bell inequality violation are given.

2002-02-19cond-mat.mes-hallcond-mat.stat-mechquant-ph

Threshold temperature for pairwise and many-particle thermal entanglement in the isotropic Heisenberg model

We study the threshold temperature for pairwise thermal entanglement in the spin-1/2 isotropic Heisenberg model up to 11 spins and find that the threshold temperature for odd and even number of qubits approaches the thermal dynamical limit from below and above, respectively. The threshold temperature in the thermodynamical limit is estimated. We investigate the many-particle entanglement in both ground states and thermal states of the system, and find that the thermal state in the four-qubit model is four-particle entangled before a threshold temperature.

2002-08-06cond-mat.mes-hallquant-ph

Quantum electrodynamics with anisotropic scaling: Heisenberg-Euler action and Schwinger pair production in the bilayer graphene

We discuss quantum electrodynamics emerging in the vacua with anisotropic scaling. Systems with anisotropic scaling were suggested by Horava in relation to the quantum theory of gravity. In such vacua the space and time are not equivalent, and moreover they obey different scaling laws, called the anisotropic scaling. Such anisotropic scaling takes place for fermions in bilayer graphene, where if one neglects the trigonal warping effects the massless Dirac fermions have quadratic dispersion. This results in the anisotropic quantum electrodynamics, in which electric and magnetic fields obey diff…

2012-03-19cond-mat.mes-hallcond-mat.str-elgr-qc

更多相关论文收起更多论文

Quantum entanglement in trimer spin-1/2 Heisenberg chains with antiferromagnetic coupling

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 Hilbert-Schmidt norm. The method is applied to the new magnetic Cu(II) trimer system, 2b.3CuCl_2.2H_2O, and to the trinuclear Cu(II) halide salt, (3MAP)_2Cu_2Cl_8. The decoherence temperature, above which the entanglement is suppressed, is determined for the both systems. A correlation among their decoherence temperatures and their respective exchange coupling consta…

2015-04-11cond-mat.mes-hallcond-mat.mtrl-scicond-mat.str-el

Aging effects in critical behavior of Heisenberg anisotropic ultrathin films

We present the results of Monte-Carlo studies of the non-equilibrium properties of ferromagnetic Heisenberg films. Aging effects were observed in non-equilibrium critical behavior. The calculations were carried out for both high-temperature and low-temperature initial states. The characteristic correlation time, which diverges at the transition temperature in the thermodynamic limit, was obtained as a function of system size and waiting time.

2023-02-09cond-mat.mes-hall

Entanglement Entropy dynamics in Heisenberg chains

By means of the time-dependent density matrix renormalization group algorithm we study the zero-temperature dynamics of the Von Neumann entropy of a block of spins in a Heisenberg chain after a sudden quench in the anisotropy parameter. In the absence of any disorder the block entropy increases linearly with time and then saturates. We analyze the velocity of propagation of the entanglement as a function of the initial and final anisotropies and compare, wherever possible, our results with those obtained by means of Conformal Field Theory. In the disordered case we find a slower (logarithmic) …

2006-03-01cond-mat.mes-hallhep-thquant-ph

Boundary and impurity effects on entanglement of Heisenberg chains

We study entanglement of a pair of qubits and the bipartite entanglement between the pair and the rest within open-ended Heisenberg $XXX$ and XY models. The open boundary condition leads to strong oscillations of entanglements with a two-site period, and the two kinds of entanglements are 180 degree out of phase with each other. The mean pairwise entanglement and ground-state energy per site in the $XXX$ model are found to be proportional to each other. We study the effects of a single bulk impurity on entanglement, and find that there exists threshold values of the relative coupling strength …

2003-12-15cond-mat.mes-hallcond-mat.stat-mech

Flux $1/f^α$ noise in 2D Heisenberg spin glasses: effects of weak anisotropic interactions

We study the dynamics of a two-dimensional ensemble of randomly distributed classical Heisenberg spins with isotropic RKKY and weaker anisotropic dipole-dipole couplings. Such ensembles may give rise to the flux noise observed in SQUIDs with a $1/f^α$ power spectrum ($α\lesssim 1$). We solve numerically the Landau-Lifshiftz-Gilbert equations of motion in the dissipationless limit. We find that Ising type fluctuators, which arise from spin clustering close to a spin-glass critical behavior with $T_c =0$, give rise to $1/f^α$ noise. Even weak anisotropic interactions lead to a crossover from the…

2014-08-26cond-mat.mes-hall

GPU-accelerated Monte Carlo simulations of anisotropic Heisenberg ferromagnets

The Monte Carlo method is a powerful technique for computing thermodynamic magnetic states of otherwise unsolvable spin Hamiltonians, but the method becomes computationally prohibitive with increasing number of spins and the simulation of real materials and nanostructures is cumbersome. This paper presents the acceleration of Monte Carlo simulations of the three-dimensional anisotropic Heisenberg model on Graphics-Processing Units (GPU). The GPU implementation of the method presented here provides an acceleration of two orders of magnitude over conventional implementations and enables the simu…

2021-06-21cond-mat.mes-hallcond-mat.stat-mechphysics.comp-ph