Monte Carlo study of the phase transition in the Critical behavior of the Ising model with shear

TL;DR

This study investigates how an external shear influences the phase transition in the Ising model, revealing a new critical behavior at high shear rates through short-time dynamical analysis.

Contribution

It introduces a novel analysis of the Ising model under shear, identifying a new critical regime and determining how shear affects the critical temperature and exponents.

Findings

Critical temperature scales with shear as $T_c \\sim \\dot{\\gamma}^\\psi$ with $\\psi=0.52(3)$

Two regimes of shear influence: growing and saturation

Discovered a new critical behavior at high shear rates

Abstract

The critical behavior of the Ising model with non-conserved dynamics and an external shear profile is analyzed by studying its dynamical evolution in the short time regime. Starting from high temperature disordered configurations (FDC), the critical temperature $T_c$ is determined when the order parameter, defined as the absolute value of the transversal spin profile, exhibits a power-law behavior with an exponent that is a combination of some of the critical exponents of the transition. For each value of the shear field magnitude, labeled as $\dot{\gamma}$, $T_c$ has been estimated and two stages have been found: 1) a growing stage at low values of $\dot{\gamma}$, where $T_c\sim\dot{\gamma}^\psi$ and $\psi=0.52(3)$; 2) a saturation regime at large $\dot{\gamma}$. The same values of $T_c(\dot{\gamma})$ were found studying the dynamical evolution from the ground state configuration (GSC) with all spins pointing in the same direction. By combining the exponents of the corresponding power laws obtained from each initial configuration the set of critical exponents was calculated. These values, at large external field magnitude, define a new critical behavior different from that of the Ising model and of other driven lattice gases.