Dimensional crossover in driving-rate induced criticality on the hysteresis-loop of disordered ferromagnetic systems

Abstract

We study the effect of finite driving rate on the nonequilibrium hysteresis-loop criticality with the systems’ nonequilateral geometry constraints allowing the dimensional crossover from three-dimensional to two-dimensional disordered ferromagnetic systems . For each system’s thickness, the disorder is fixed above the critical line for adiabatic driving, such that the emergent critical behaviors are solely attributed to the increased driving rates of the external field.We demonstrate it by computing the pertaining magnetizations and coercive fields, changes in avalanche distributions and shapes, and correlation functions of spin-flip events where the pace of the field increments are varied in a broad range. Our results reveal that the driving field rate profoundly affects system evolution attaining three distinct regimes of the induced criticality at the proper thickness-dependent rate values. In particular, these regimes are characterized by the occurrence of non-spanning avalanches (slow driving), the first appearance of spanning avalanches (intermediate regime), and being overwhelmed by system-spanning avalanches (fast driving regime) for a given thickness. Our results will bring some critical insights to the theoretical and experimental studies on the field-driven nonequilateral systems both for conceptual reasons and the versatility of their applications..