Applied Physics Seminar

Future cryogenically cooled space telescopes will provide exciting opportunities for the far-IR spectroscopy. This drives an interest to direct detectors whose sensitivity would be adequate to the ultra low radiation background. Superconducting bolometers are among the most promising approaches. However, in order to reach the fundamental limit in space set by the photon shot noise from the cosmic infrared background, their sensitivity must be increased by a factor of ~ 100 compared to the state-of-the-art. We develop a unique version of the bolometer whose thermal isolation is due to the weak electron-phonon coupling in a small volume of the superconducting film. Recent optical tests have demonstrated the extremely low detector noise equivalent power NEP ≈ 10-19 W/Hz1/2 and the ability of the bolometer to operate as an infrared calorimeter with an energy resolution ~ 0.1 eV. I will discuss the potential of such a photon detector to achieve useful energy resolution while detecting single THz photons.