Stability mechanisms of high current transport in iron-chalcogenides superconducting films

TL;DR

This paper investigates the stability mechanisms of high current transport in iron-chalcogenide superconducting films, focusing on flux flow instabilities to enhance their application potential.

Contribution

It provides experimental analysis of flux flow instabilities in Fe(Se,Te) films, identifying whether they are thermal or electronic in nature, advancing understanding of current stability.

Findings

Flux flow instabilities observed in Fe(Se,Te) films.

Analysis suggests the nature of instabilities, aiding in improving current capacity.

Results support models explaining flux flow behavior in iron-chalcogenides.

Abstract

The improvement in the fabrication techniques of iron-based superconductors have made these materials real competitors of high temperature superconductors and MgB$_2$. In particular, iron-chalcogenides have proved to be the most promising for the realization of high current carrying tapes. But their use on a large scale cannot be achieved without the understanding of the current stability mechanisms in these compounds. Indeed, we have recently observed the presence of flux flow instabilities features in Fe(Se,Te) thin films grown on CaF$_2$. Here we present the results of current-voltage characterizations at different temperatures and applied magnetic fields on Fe(Se,Te) microbridges grown on CaF$_2$. These results will be analyzed from the point of view of the most validated models with the aim to identify the nature of the flux flow instabilities features (i.e., thermal or electronic), in order to give a further advance to the high current carrying capability of iron-chalcogenide superconductors.