Vortex core deformation and stepper motor behavior in a superconducting ratchet

TL;DR

This paper explores the frequency-dependent behavior of superconducting vortex ratchets, revealing a transition from vortex rectification to phase slip line rectification and modeling the high-frequency stepper motor behavior.

Contribution

It provides experimental and theoretical insights into vortex dynamics, highlighting a transition in rectification mechanisms and introducing a model for high-frequency vortex motion.

Findings

High frequency vortex behavior resembles a particle in a periodic potential.

Transition from Abrikosov vortex to phase slip line rectification occurs at low frequencies.

Hysteretic behavior and increased rectified voltage characterize the transition.

Abstract

We investigated experimentally the frequency dependence of a superconducting vortex ratchet effect by means of electrical transport measurements and modeled it theoretically using the time dependent Ginzburg-Landau formalism. We demonstrate that the high frequency vortex behavior can be described as a discrete motion of a particle in a periodic potential, i.e. the so called stepper motor behavior. Strikingly, in the more conventional low frequency response a transition takes place from an Abrikosov vortex rectifier to a phase slip line rectifier. This transition is characterized by a strong increase in the rectified voltage and the appearance of a pronounced hysteretic behavior.