Stability Mechanisms of High Current Transport in Iron-Chalcogenide Superconducting Films

The improvement in the fabrication techniques of iron-based superconductors has 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. However, 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 advance further to the high current-carrying capability of iron-chalcogenide superconductors.