Pinning time statistics for vortex lines in disordered environments

TL;DR

This paper investigates the statistical properties of vortex line pinning times in disordered superconductors through numerical simulations, revealing power law distributions and differences based on disorder models.

Contribution

It introduces a detailed numerical analysis of pinning time distributions for vortex lines, comparing different disorder models and their impact on pinning dynamics.

Findings

Pinning time distributions follow power laws in the pinned phase.

Disorder models significantly affect the scaling exponents.

Short-time behavior varies notably between models.

Abstract

We study the pinning dynamics of magnetic flux (vortex) lines in a disordered type-II superconductor. Using numerical simulations of a directed elastic line model, we extract the pinning time distributions of vortex line segments. We compare different model implementations for the disorder in the surrounding medium: discrete, localized pinning potential wells that are either attractive and repulsive or purely attractive, and whose strengths are drawn from a Gaussian distribution; as well as continuous Gaussian random potential landscapes. We find that both schemes yield power law distributions in the pinned phase as predicted by extreme-event statistics, yet they differ significantly in their effective scaling exponents and their short-time behavior.