Speaker
Description
MgB2 thin films grown by hybrid physical-chemical vapor deposition (HPCVD) have been investigated for SRF cavity applications. Clean MgB2 thin films have a low residual resistivity (<0.1 µΩcm) and a high Tc of 40 K, promising a low BCS surface resistance. Its thermodynamic critical field Hc is higher than Nb, potentially leading to a higher maximum accelerating filed. The lower critical field Hc1, which marks the vortex penetration into the superconductor and the vortex motion related dissipation, is lower for MgB2 than Nb, but it can be enhanced by decreasing the film thickness. I will present results on the enhancement of Hc1 in thin MgB2 films and coatings, deposition of MgB2 films on Cu, and the coating of RF cavities by MgB2. These results are encouraging for the application of MgB2 for SRF cavities.
