The Quadrupole Resonator, Design Considerations and Layout of a New Instrument for the RF Characterization of Superconducting Surface Samples

A disk-shaped superconducting sample is welded onto an Nb support cylinder and exposed to the magnetic RF field of a four-wire transmission line resonator. The fields on the cylinder wall decay in a c ut-off like fashion in such a way that they perturb the measurement very little. RF dissipation of the disk is determined by substitution with a d.c. heater on the back of the sample which is made to produce the same temperature rise, controlled by thermometers.