On-chip diagnostic equipment for 100 GHz superconducting circuits

A set of on-chip tools was developed for evaluating superconducting millimeter-wave circuits including: (1) a voltage-standing-wave-ratio (VSWR) reflectometer, (2) a phase meter, (3) a transmission line velocity meter, (4) a transmission line inductance meter, and (5) a double balanced mixer. The circuits consist of pure Nb conductors and Nb/AlO/sub x//Nb superconductor-insulator-superconductor junctions. A report is presented on the design and use of the VSWR probe, which has not appeared in the literature, and the use of the velocity meter, the design for which has previously been reported.