Submillimeter-Wave Mixing and Noise in High-Temperature Josephson Junctions

摘要

A breadboard Josephson submillimeter-wave mixer is designed and investigated. The best value of the mixer noise temperature for this device has been demonstrated as 1100 K at frequencies of 400-500 GHz. Josephson mixers are shown to be promising and competitive with Schottky-barrier diodes (SBDs). Excess noise associated with the multiple Andreev reflection in the microshorts in the junction area is discovered.