Experimental evidence for a large critical transverse depinning force in weakly-pinned vortices

TL;DR

This paper provides experimental evidence that weakly-pinned superconducting vortices exhibit a significantly large critical force for transverse depinning, especially when influenced by a longitudinal drive, revealing complex vortex dynamics.

Contribution

It demonstrates the existence of a large transverse critical depinning force in weakly-pinned superconductors using combined ac and dc drives, a novel experimental approach.

Findings

Large transverse depinning force observed

Transverse force is enhanced by longitudinal drive

Separated transverse and longitudinal depinning forces

Abstract

We present experimental evidence for the existence of a large critical transverse depinning force. These results are obtained in the weakly-pinned superconducting metal glasses Fe$_{x}$Ni$_{1-x}$Zr$_{2}$ using crossed ac and dc driving currents. We study the depinning force due to the transverse ac drive as a function of a longitudinal dc drive. The ac/dc combination allows us to separate the transverse drive from the longitudinal one. We show that the force required for depinning in the transverse direction is enhanced by a longitudinal drive, which leads to the existence of a large transverse critical force.