Title :
Measurements of the Riedel peak in superconducting aluminum tunnel junctions (mixers)
Author_Institution :
Dept. of Phys., Chalmers Univ. of Technol., Goteborg, Sweden
fDate :
3/1/1993 12:00:00 AM
Abstract :
The Riedel singularity in thin-film aluminum tunnel junctions was measured from temperature behavior of the zero voltage step and the RF-induced Josephson steps at around the gap frequency. From these experiments the author derived a value of the imaginary gap parameter to be about 1% of the gap parameter value at the gap edge when the temperature was 0.7 of the transition temperature. The author believes that, using magnetic field for tuned superconductor-insulator-superconductor (SIS) mixers with relatively large area, the Riedel singularity should not play an important role for frequencies around the gap frequency at finite temperatures.<>
Keywords :
Josephson effect; aluminium; microwave detectors; mixers (circuits); quasi-particles; receivers; submillimetre wave devices; superconducting junction devices; superconducting microwave devices; type I superconductors; Al tunnel junction; RF-induced Josephson steps; Riedel peak; Riedel singularity; gap frequency; imaginary gap parameter; superconducting junctions; superconductor-insulator-superconductor mixers; temperature behavior; zero voltage step; Aluminum; Frequency measurement; Josephson junctions; Magnetic fields; Radio frequency; Superconducting devices; Superconducting thin films; Superconducting transition temperature; Temperature measurement; Voltage;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
