Finite Size Scaling analysis of the avalanches in the 3d Gaussian Random Field Ising Model with metastable dynamics

TL;DR

This paper performs a finite size scaling analysis of avalanches in the 3D Gaussian Random Field Ising Model at zero temperature, revealing different avalanche types and their scaling behavior as system size increases.

Contribution

It introduces a detailed classification of avalanches and identifies their critical and supercritical/subcritical types through finite-size scaling analysis.

Findings

Identification of critical and supercritical avalanches

Different scaling exponents for avalanche types

Scenario for avalanche behavior in the thermodynamic limit

Abstract

A numerical study is presented of the 3d Gaussian Random Field Ising Model at T=0 driven by an external field. Standard synchronous relaxation dynamics is employed to obtain the magnetization versus field hysteresis loops. The focus is on the analysis of the number and size distribution of the magnetization avalanches. They are classified as being non-spanning, 1d-spanning, 2d-spanning or 3d-spanning depending on whether or not they span the whole lattice in the different space directions. Moreover, finite-size scaling analysis enables identification of two different types of non-spanning avalanches (critical and supercritical) and two different types of 3d-spanning avalanches (critical and subcritical), whose numbers increase with L as a power-law with different exponents. We conclude by giving a scenario for the avalanches behaviour in the thermodynamic limit.