Superconductive bolometers for submillimeter wavelengths

摘要: Three types of composite superconductive bolometers are described in which the temperature‐sensitive element is a superconducting film at transition temperature, superconductor–normal metal–superconductor Josephson junction, or superconductor–insulator–normal metal quasiparticle tunneling junction. The evaporated onto sapphire substrate on reverse side bismuth to absorb submillimeter radiation. noise limitations each type bolometer calculated. fabrication and measured performance transition‐edge Josephson‐junction described. best electrical (noise‐equivalent power) NEP obtained with fabricated 4×4×0.005‐mm (1.7±0.1) ×10−15 W Hz−1/2 2 Hz an operating temperature 1.27 K. This within factor thermal limit. effective absorptivity be 0.47±0.05, co...