Journal of Physics Conference Series

Simulation of non-equilibrium critical behavior of the 3D isotropic and anisotropic Heisenberg models

Vladimir V. Prudnikov, Pavel Vladimirovich Prudnikov, Evgenii A. Pospelov, Лях Анастасия Сергеевна

Published Jan 1, 2021• 0 citations

Abstract

Abstract Monte Carlo study of non-equilibrium critical behavior of three-dimensional Heisenberg model in isotropic case and with anisotropy of easy axis type is carried out. Relaxational Glauber-like dynamics of these models with evolution from high-temperature initial state is investigated. Realization of aging is demonstrated for two-time dependence of the autocorrelation function and dynamical susceptibility. Asymptotic fluctuation-dissipation ratios are determined for isotropic X ∞ = 0.383(6) and anisotropic X ∞ = 0.392(7) Heisenberg models. Significant influence of easy-axis anisotropy on non-equilibrium critical behavior of the 3D Heisenberg model leading to characteristics typical for the 3D Ising model is revealed.

DOI: 10.1088/1742-6596/1740/1/012004

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