Superconducting tunnel diodes (SISs) are investigated for both the generation and detection of submillimeter wavelengths. For detection, heterodyne receivers using SISs are investigated. Josephson currents are found to have a large effect on SIS mixers in the submillimeter, even though their effect is less at lower frequencies. At 492 GHz, fixer conversion gain increased by 4 dB when Josephson currents are not suppressed by a magnetic field. A much higher noise is seen in this gain mode, but further investigation of this recently discovered phenomenon is warranted. For submillimeter generation, a two-dimensional array of SISs is investigated. The ac Josephson effect in the SIS is expected to deliver submillimeter power into a free-space radiation mode traveling perpendicular to the array. No experimental devices have been developed yet, but the authors show computer simulations and microwave scale model measurements of array structures.

Date Published: 1 July 1991
PDF: 12 pages
Proc. SPIE 1477, Superconductivity Applications for Infrared and Microwave Devices II, (1 July 1991); doi: 10.1117/12.45611

Published in SPIE Proceedings Vol. 1477:
Superconductivity Applications for Infrared and Microwave Devices II
Vernon O. Heinen; Kul B. Bhasin, Editor(s)