English
Related papers

Related papers: Real-time energy dynamics in spin-1/2 Heisenberg c…

200 papers

We study the energy transport in a system of two half-infinite XXZ chains initially kept separated at different temperatures, and later connected and let free to evolve unitarily. By changing independently the parameters of the two halves,…

Statistical Mechanics · Physics 2016-06-01 Alberto Biella , Andrea De Luca , Jacopo Viti , Davide Rossini , Leonardo Mazza , Rosario Fazio

We have considered a numerical scheme for the calculation of the equilibrium properties of spin-1/2 XY chains. Within its frames it is necessary to solve in the last resort only the 2N\times 2N eigenvalue and eigenvector problem but not the…

Statistical Mechanics · Physics 2007-05-23 Oleg Derzhko , Taras Krokhmalskii

We revisit the so-called folded XXZ model, which was treated earlier by two independent research groups. We argue that this spin-1/2 chain is one of the simplest quantum integrable models, yet it has quite remarkable physical properties.…

Statistical Mechanics · Physics 2021-10-13 Balázs Pozsgay , Tamás Gombor , Arthur Hutsalyuk , Yunfeng Jiang , Levente Pristyák , Eric Vernier

We consider the increase of the spatial variance of some inhomogeneous, non-equilibrium density (particles, energy, etc.) in a periodic quantum system of condensed matter-type. This is done for a certain class of initial quantum states…

Statistical Mechanics · Physics 2009-10-23 Robin Steinigeweg , Hannu Wichterich , Jochen Gemmer

The dynamics of individual colloidal particles in random potential energy landscapes were investigated experimentally and by Monte Carlo simulations. The value of the potential at each point in the two-dimensional energy landscape follows a…

We report on {\it ab initio} time-dependent spin dynamics simulations for a two-center magnetic molecular complex based on time-dependent non-collinear spin density functional theory. In particular, we discuss how the dynamical behavior of…

Other Condensed Matter · Physics 2015-06-16 Maria Stamenova , Stefano Sanvito

We address the computation of the Loschmidt echo in interacting integrable spin chains after a quantum quench. We focus on the massless regime of the XXZ spin-1/2 chain and present exact results for the dynamical free energy (Loschmidt echo…

Statistical Mechanics · Physics 2018-07-09 Lorenzo Piroli , Balázs Pozsgay , Eric Vernier

The magnetic and thermodynamic properties of spin-1/2 Heisenberg diamond chains are investigated in three different cases: (a) J1, J2, J3>0 (frustrated); (b) J1, J3<0, J2>0 (frustrated); and (c) J1, J2>0, J3<0 (non-frustrated). The density…

Strongly Correlated Electrons · Physics 2009-11-13 Bo Gu , Gang Su

The spin 1/2 XXZ chain in a random magnetic field pointing in the Z direction is numerically studied using the Density Matrix Renormalization Group (DMRG) method. The phase diagram as a function of the anisotropy of the XXZ Hamiltonian and…

Strongly Correlated Electrons · Physics 2009-11-07 Laura Urba , Anders Rosengren

We study the one-dimensional $S=1/2$ Heisenberg model with a uniform and a staggered magnetic fields, using the dynamical density-matrix renormalization group (DDMRG) technique. The DDMRG enables us to investigate the dynamical properties…

Strongly Correlated Electrons · Physics 2007-10-19 S. Nishimoto , M. Arikawa

We study gapless quantum spin chains with spin 1/2 and 1: the Fredkin and Motzkin models. Their entangled groundstates are known exactly but not their excitation spectra. We first express the groundstates in the continuum which allows for…

Strongly Correlated Electrons · Physics 2017-10-25 Xiao Chen , Eduardo Fradkin , William Witczak-Krempa

The density matrix renormalization group method is generalized to one dimensional random systems. Using this method, the energy gap distribution of the spin-1/2 random antiferromagnetic Heisenberg chain is calculated. The results are…

Condensed Matter · Physics 2009-10-28 Kazuo Hida

Using the adaptive time-dependent density-matrix renormalization group method for the 1D Hubbard model, the splitting of local perturbations into separate wave packets carrying charge and spin is observed in real-time. We show the…

Other Condensed Matter · Physics 2007-05-23 C. Kollath , U. Schollwoeck , W. Zwerger

We investigate the out-of-equilibrium dynamics after a local quench that connects two spin-1/2 XXZ chains prepared in the ground state of the Hamiltonian in different phases, one in the ferromagnetic phase and the other in the critical…

Strongly Correlated Electrons · Physics 2017-01-19 A. L. de Paula , H. Bragança , R. G. Pereira , R. C. Drumond , M. C. O. Aguiar

We study the ballistic-to-diffusive transition induced by the weak breaking of integrability in a boundary-driven XXZ spin-chain. Studying the evolution of the spin current density $\mathcal J^s$ as a function of the system size $L$, we…

Statistical Mechanics · Physics 2020-12-18 João S. Ferreira , Michele Filippone

In this paper, we study the mechanics of statistically non-uniform two-phase elastic discrete structures. In particular, following the methodology proposed in (Luciano and Willis, Journal of the Mechanics and Physics of Solids 53,…

Materials Science · Physics 2011-05-03 Jan Zeman , Ron H. J. Peerlings , Marc G. D. Geers

We study the nature of collective excitations in harmonic chains with masses exhibiting long-range correlated disorder with power spectrum proportional to $1/k^{\alpha}$, where $k$ is the wave-vector of the modulations on the random masses…

Disordered Systems and Neural Networks · Physics 2009-11-07 F. A. B. F. de Moura , M. D. Coutinho-Filho , E. P. Raposo , M. L. Lyra

We provide a detailed comparison between the dynamics of high-temperature spatiotemporal correlation functions in quantum and classical spin models. In the quantum case, our large-scale numerics are based on the concept of quantum…

Statistical Mechanics · Physics 2022-12-01 Tjark Heitmann , Jonas Richter , Fengping Jin , Kristel Michielsen , Hans De Raedt , Robin Steinigeweg

The equilibrium dynamics of the spin-1/2 XX chain is re-examined within a recently developed formalism based on the quantum transfer matrix and a thermal form factor expansion. The transversal correlation function is evaluated in real time…

Statistical Mechanics · Physics 2019-10-29 Frank Göhmann , Karol K. Kozlowski , Jesko Sirker , Junji Suzuki

Combining high-temperature expansions with the recursion method and quantum Monte Carlo simulations with the maximum entropy method, we study the dynamics of the spin-1/2 Heisenberg chain at temperatures above and below the coupling J. By…

Strongly Correlated Electrons · Physics 2009-10-30 O. A. Starykh , A. W. Sandvik , R. R. P. Singh