Injection-Detection Experiments in All Aluminum 1-D Imaging Spectrometers Based on Superconducting Tunnel Junctions

We report on a class of low temperature radiation detectors based on superconducting tunnel junctions (STJs) in which the incoming radiation is absorbed in a long superconducting strip while the readout operation occurs at the two ends of the strip, where two STJs are laterally positioned. These Distributed Read-Out Imaging Devices, or DROIDs, provide spectroscopy, 1-D imaging, single-photon sensitivity, and high quantum efficiency, all in one device. Typically these devices are realized by using Tantalum for the absorber strip and Aluminum for the two STJs. In this way the quasi-particles are created in the Tantalum and subsequently trapped in the Aluminum.