Superconducting properties of corner-shaped Al microstrips

TL;DR

This study investigates how corner geometries in aluminum superconducting microstrips influence vortex behavior and electrical properties, revealing asymmetric vortex dynamics and voltage rectification effects due to sharp turns.

Contribution

It demonstrates the impact of corner geometry on vortex dynamics and critical current enhancement, providing experimental evidence for theoretical predictions.

Findings

Asymmetric vortex penetration at sharp corners

Voltage rectification in corner-shaped strips

Critical current enhancement at specific field-current conditions

Abstract

The electrical transport properties of corner-shaped Al superconducting microstrips have been investigated. We demonstrate that the sharp turns lead to asymmetric vortex dynamics, allowing for easier penetration from the inner concave angle than from the outer convex angle. This effect is evidenced by a strong rectification of the voltage signal otherwise absent in straight superconducting strips. At low magnetic fields, an enhancement of the critical current with increasing magnetic field is observed for a particular combination of field and current polarity, confirming a recently theoretically predicted competing interplay of superconducting screening currents and applied currents at the inner side of the turn.