We have built and demonstrated an all superconductive digital readout for use in an IR focal plane array sensor. High performance, ultralow power superconductive circuits perform the functions of low noise preamplification and analog to digital conversion. The superconductive readout was tested with a variety of detectors, including InSb, Si:As, and a thin film NbN superconducting detector. Light sources included a HeNe laser (0.6 micron), a CO2 laser (10 microns), and a blackbody (400 to 900 K). In each case, the detector and readout circuitry was assembled into a 2 inch diameter, 6 inch long test package cooled in a single dewar. We demonstrated the functionality of the detector/readout channel from input photons to output digital signal. The superconductive readout reported here used Nb-based circuits operating at 4 K. An NbN squid amplifier and detector have subsequently been demonstrated above 10 K. We discuss the extension of the entire digital readout to operating temperatures above 10 K.

Date Published: 1 July 1992
PDF: 10 pages
Proc. SPIE 1684, Infrared Readout Electronics, (1 July 1992); doi: 10.1117/12.60504

Published in SPIE Proceedings Vol. 1684:
Infrared Readout Electronics
Eric R. Fossum, Editor(s)