Superconducting film with randomly magnetized dots: A realization of the 2D XY model with random phase shifts

TL;DR

This paper demonstrates that a thin superconducting film with randomly magnetized dots acts as an experimental realization of the 2D XY model with random phase shifts, showing the persistence of superconductivity under small disorder.

Contribution

It introduces a physical system that models the 2D XY model with disorder, providing experimental insights into its phase behavior.

Findings

Superconducting phase persists with small disorder.

Magnetized dots create a disordered pinning potential.

System models the 2D XY model with random phase shifts.

Abstract

We consider a thin superconducting film with randomly magnetized dots on top of it. The dots produce a disordered pinning potential for vortices in the film. We show that for dots with permanent and random magnetization normal or parallel to the film surface, our system is an experimental realization of the two-dimensional XY model with random phase shifts. The low-temperature superconducting phase, that exists without magnetic dots, survives in the presence of magnetic dots for sufficiently small disorder.