Finite-temperature avalanches in 2D disordered Ising models

Abstract

We study the qualitative and quantitative properties of the Barkhausen noise emerging at finite temperatures in random Ising models. The random-bond Ising Model is studied with a Wolff cluster Monte-Carlo algorithm to monitor the avalanches generated by an external driving magnetic field. Satisfactory power-law distributions are found which expand over five decades, with a temperature-dependent critical exponent which matches the existing experimental measurements. We also focus on a Ising system in which a finite fraction of defects is quenched. Also the presence of defects proves able to induce a critical response to a slowly oscillating magnetic field, though in this case the critical exponent associated with the distributions obtained with different defect fractions and temperatures seems to belong to the same universality class, with a critical exponent equal to 1.

14 pages, 6 figures

References in corpus (4)

• Dynamic phase transition in the two-dimensional kinetic Ising model in an oscillating field: Universality with respect to the stochastic dynamic
• Universality in disordered systems: The case of the three-dimensional random-bond Ising model
• Temperature-dependent criticality in random 2D Ising models
• The Effect of Defects on Magnetic Droplet Nucleation

Cited by in corpus (3)

• Anomalous distribution of magnetization in an Ising spin glass with correlated disorder
• Dynamic Phase Transition in 2D Ising Systems: Effect of Anisotropy and Defects
• Inter-Event Time Power Laws in Heterogeneous Systems