SINIS Detectors: 30 Years of Achievements and Delusions

Superconductor-Insulator-Normal metal Insulator-Superconductor (SINIS) structure with NIS tunnel junctions is a generic element for Andreev bolometers, normal metal hot electron bolometers, cold electron bolometers, electron coolers, cryogenic thermometers, etc. Past 30 years such devices intended mainly for microwave detection were developed both theoretically and experimentally. Some of results and conclusions are contradictive. Here we briefly review main experimental results and possible mechanisms of SINIS microwave detectors operation, influence of electron cooling, normal metal traps, nonequilibrium effects, quantum absorption and bolometric absorption, energy dissipation by phonons and electrons. Crucial issue for practical detector is proper integration with planar antenna array that determine coupling efficiency, beampattern, bandwidth. We compare two main approaches with modelling of infinite array with periodic boundary conditions and modelling of the entire moderate array. Comparison with experiments support the approach with modelling of the whole array and taking into account the different boundary conditions between adjacent antennas. Correct experimental study requires cryogenic bandpass filter and integrating cavity.