The accelerating systems of both the FCC-ee and FCC-hh will make use of thin-film coated copper cavities. The FCC study aims at minimizing the overall energy consumption and for this particular purpose we aim at replacing the standard niobium thin film coatings by A15 family materials such as Nb3Sn for SRF applications, with the final goal of improving the quality factor of the FCC accelerating cavities by a factor ten compared to the present state-of-the-art. The collaboration with TU-Wien will focus on correlating the film growth conditions, their superconducting and structural properties.

The group of Low Temperature Physics and Superconductivity at the Atominstitut (ATI) of TU-Wien will perform analyses by Scanning Hall Probe microscopy (SHPM) in order to assess the local properties of the elaborated films. The aim of the study will be to identify the local effect of the biasing voltage used during the coating as well as the effect of the thermal treatment in order to optimize the coating recipe. Flux penetration will be monitored globally by SQUID magnetometry and locally by SHPM. Areas with particular high or low stability against flux penetration will be identified for further microstructural investigations. This works will be performed by ATI-TU-Wien by a PhD student supported by the scientific and technical staff.