A Simple Model of Superconducting Vortex Avalanches

TL;DR

This paper presents a simple lattice model for superconducting vortex avalanches, revealing critical behavior with universal scaling exponents and self-organized criticality at large scales.

Contribution

It introduces a minimal lattice model capturing vortex avalanche dynamics and identifies universal critical exponents for the system's critical state.

Findings

Avalanches span all length scales up to system size.

Four universal critical exponents are determined: tau, D, z, tau_t.

The model exhibits self-organized criticality in vortex dynamics.

Abstract

We introduce a simple lattice model of superconducting vortices driven by repulsive interactions through a random pinning potential. The model describes the behavior at the scale of the London length lambda or larger. It self-organizes to a critical state, characterized by a constant flux density gradient, where the activity takes place in terms of avalanches spanning all length scales up to the system size. We determine scaling relations as well as four universal critical exponents for avalanche moments and durations: tau = 1.63 +/- 0.02, D = 2.7 +/- 0.1, z = 1.5 +/- 0.1, and tau_t = 2.13 +/- 0.14, for the system driven at the boundary.