Analysis of spin avalanches due to interplay of disorder and temperature

Abstract

The nonequilibrium zero-temperature Random Field Ising Model (RFIM) has been extensively studied to understand critical response and avalanches in disordered driven systems. The emergence of power-law behaviour is observed over a wide region around the critical point. These studies however, are confined to zero-temperature dynamics. We study the role of temperature, which is inevitable in real experiments, in the context of RFIM on triangular lattices. We explore the interplay of different parameters: temperature, random field strength, and relaxation time which affect the prevalence of power-law behaviour on the lattice. The results indicate that power-law survives only in the regime of low temperature or small and intermediate disorder. Variations in temperature and disorder have similar affects on the avalanche-size distribution, indicating their strong correspondence. We also discuss the process of blurring out of the power law on increasing temperature or disorder.