Domain Growth in Ising Systems with Quenched Disorder

TL;DR

This study uses Monte Carlo simulations to analyze domain growth in disordered Ising systems, revealing power-law growth with exponents influenced by temperature and disorder, aligning with theoretical predictions.

Contribution

It provides the first comprehensive Monte Carlo analysis of domain growth in quenched disordered Ising models with both nonconserved and conserved dynamics.

Findings

Power-law domain growth observed with exponents depending on T and ε.

Exponents match theoretical predictions based on energy barrier models.

Results applicable to ferromagnets and binary mixtures with quenched disorder.

Abstract

We present results from extensive Monte Carlo (MC) simulations of domain growth in ferromagnets and binary mixtures with quenched disorder. These are modeled by the "random-bond Ising model" and the "dilute Ising model" with either nonconserved (Glauber) spin-flip kinetics or conserved (Kawasaki) spin-exchange kinetics. In all cases, our MC results are consistent with power-law growth with an exponent $\theta (T,\epsilon)$ which depends on the quench temperature $T$ and the disorder amplitude $\epsilon$. Such exponents arise naturally when the coarsening domains are trapped by energy barriers which grow logarithmically with the domain size. Our MC results show excellent agreement with the predicted dependence of $\theta (T,\epsilon)$.