Current-driven transformations of the intermediate state patterns in type-I superconductors

TL;DR

This study investigates how applying large currents affects the intermediate state patterns in type-I superconductors, revealing a transition from laminar to tubular flux structures and discussing the phase diagram.

Contribution

It demonstrates that high currents can eliminate topological hysteresis and alter flux patterns, providing new insights into the dynamic behavior of the intermediate state in type-I superconductors.

Findings

Large currents transform laminar flux structures into tubular ones.

Flux tube size and distribution differ between static and dynamic regimes.

Phase diagram includes temperature, magnetic field, and current effects.

Abstract

Dynamic structure of the intermediate state was studied in pinning-free thick Pb strips using real-time magneto-optical visualization. It is found that topological hysteresis can be lifted by applying sufficiently large current. Namely, laminar structure that appears on flux exit in a static case is turned into tubular when the sufficiently large transport current is present. Size and distribution of the flux tubes in static and dynamic regimes are different. Temperature, magnetic field and current phase diagram is discussed.