Non-Thermal Absorption and Quantum Efficiency of SINIS Bolometer

We study mechanisms of absorption in two essentially different types superconductor-insulator-normal metal-insulator-superconductor (SINIS) bolometers with absorber directly placed on Si wafer and suspended above the substrate. The figure merit for quantum photon is efficiency equal to number detected electrons one photon. dramatically dependent phonon losses substrate electrodes, electron energy electrodes through tunnel junctions. maximum can approach n = xmlns:xlink="http://www.w3.org/1999/xlink">hf/kT 160 at f 350 GHz T 0.1 K, current responsivity d xmlns:xlink="http://www.w3.org/1999/xlink">I /d xmlns:xlink="http://www.w3.org/1999/xlink">P xmlns:xlink="http://www.w3.org/1999/xlink">e/kT gain bolometer case, contrary counter mode n 1 xmlns:xlink="http://www.w3.org/1999/xlink">e/hf . In experiments, we intrinsic up 80 per absorber, about case Cu Pd Kapitsa resistance protect from power leak Al electrodes.