Vortex dynamics in superconducting channels with periodic constrictions

TL;DR

This paper investigates how vortices in superconducting channels with periodic constrictions behave under varying magnetic fields, revealing oscillations, hysteresis effects, and the influence of channel geometry on vortex dynamics.

Contribution

It provides new insights into vortex behavior in superconducting channels with periodic constrictions, highlighting the effects of geometry and screening on vortex motion and hysteresis.

Findings

Critical current oscillations depend on channel shape and arrangement.

Hysteresis occurs due to vortex pinning outside channels at high fields.

Dynamical hysteresis observed near matching fields.

Abstract

Vortices confined to superconducting easy flow channels with periodic constrictions exhibit reversible oscillations in the critical current at which vortices begin moving as the external magnetic field is varied. This commensurability scales with the channel shape and arrangement, although screening effects play an important role. For large magnetic fields, some of the vortices become pinned outside of the channels, leading to magnetic hysteresis in the critical current. Some channel configurations also exhibit a dynamical hysteresis in the flux-flow regime near the matching fields.