Fabrication and Physical Properties of Polycrystalline Iron-Chalcogenides Superconductors

Iron-based superconductors are an interesting class
of materials that have attracted significant interest during the last
years, and which could be employed in a variety of potential applications
due to their high upper critical field Hc2 . In order to
exploit the properties of these materials for practical applications,
in this paper we explore two different routes for the fabrication of
polycrystalline samples belonging to 11-family. In particular, the
influence of dedicated heat treatments has been investigated to optimize
their overall superconducting properties. Then, we compared
the pinning properties of these two types of samples to correlate
the fabrication process with the pinning landscape. The final aim
is to obtain an increased Tc and Hc2 , as well as an enhanced pinning
efficacy, which could lead to higher critical current density Jc
relevant for practical uses