Current driven pinning strength in the vortex lattice of Nb3Sn aided by a small oscillating magnetic field

TL;DR

This study investigates how a small oscillating magnetic field influences vortex pinning in Nb3Sn, revealing history-dependent voltage patterns and a mysterious step feature in I-V curves.

Contribution

It demonstrates that a small oscillating magnetic field can induce a peak-effect-like pattern and memory effects in Nb3Sn's vortex lattice, a novel insight into vortex dynamics.

Findings

Voltage dip similar to peak-effect observed

History-dependent pattern with memory effect

Step feature at high shaking-field amplitude

Abstract

By the application of a small oscillating magnetic field parallel to the main magnetic field and perpendicular to the transport current, we were able to generate a voltage dip in the I-V curves of Nb$_3$Sn similar to the peak-effect pattern observed in earlier resistivity measurements. The pattern was history dependent and exhibited a memory effect. In addition we observed in the I-V curves for a high shaking-field amplitude a step feature of unknown origin.