Anomalous switching in Nb/Ru/Sr2RuO4 topological junctions by chiral domain wall motion

TL;DR

This paper demonstrates that Nb/Ru/Sr2RuO4 topological superconducting junctions exhibit anomalous switching behavior driven by chiral domain wall motion, suggesting potential for novel superconducting device applications.

Contribution

It provides experimental evidence linking chiral domain wall dynamics to switching phenomena in topological superconducting junctions, a novel insight in superconductor physics.

Findings

Switching between critical current states explained by chiral-domain-wall dynamics

Switching behavior can be controlled by temperature, magnetic field, and current

Results suggest potential for superconducting device applications based on domain wall motion

Abstract

A spontaneous symmetry breaking in a system often results in domain wall formation. The motion of such domain walls is utilized to realize novel devices like racetrack-memories, in which moving ferromagnetic domain walls store and carry information. Superconductors breaking time reversal symmetry can also form domains with degenerate chirality of their superconducting order parameter. Sr2RuO4 is the leading candidate of a chiral p-wave superconductor, expected to be accompanied by chiral domain structure. Here, we present that Nb/Ru/Sr2RuO4 topological superconducting-junctions, with which the phase winding of order parameter can be effectively probed by making use of real-space topology, exhibit unusual switching between higher and lower critical current states. This switching is well explained by chiral-domain-wall dynamics. The switching can be partly controlled by external parameters such as temperature, magnetic field and current. These results open up a possibility to utilize the superconducting chiral domain wall motion for future novel superconducting devices.