Speaker
Description
A cost-effective facility for testing planar thin film samples under RF conditions has recently been commissioned at Daresbury Laboratory. This facility utilises a bulk Nb choked test cavity operating at 7.8 GHz, housed within a dry, liquid helium free cryostat. It is used to make low power surface resistance measurements of 10 cm diameter samples at temperatures down to 4 K and sample surface magnetic fields up to 1 mT. The main advantage of this system is the simple sample mounting procedure due to no physical welding between the sample and test cavity. This allows for testing of 2-3 samples per week. Given this high throughput rate, we are able to quickly identify which samples are performing well under RF conditions and should require further testing at higher gradient. After RF characterisation, the superconducting DC properties of these samples as well as surface analysis will be made using other facilities at Daresbury. Details of this facility as well as recent measurements of both bulk Nb and thin film coated samples will be presented.
