Anomalous flux avalanche morphology in a a-MoGe superconducting film with a square antidot lattice - experiment and simulation

TL;DR

This study visualizes and simulates flux avalanches in a superconducting a-MoGe film with a square antidot lattice, revealing unique tree-like avalanche patterns with branches at 45 degrees.

Contribution

It combines magneto-optical imaging and numerical simulations to uncover novel flux avalanche morphologies in patterned superconducting films.

Findings

Avalanches form tree-like structures with branches at 45 degrees.

The observed avalanche patterns are confirmed by simulations.

Flux behavior is influenced by the square antidot lattice geometry.

Abstract

We have employed magneto-optical imaging to visualize the occurrence of flux avalanches in a superconducting film of a-MoGe. The specimen was decorated with square antidots arranged in a square lattice. We observed avalanches with the anomalous habit of forming trees where the trunk is perpendicular to the main axis of the square lattice, whereas the branches form angles of 45 degrees. The overall features of the avalanches, and in particular the 45 degree direction of the branches, were confirmed by numerical simulations.