Near-Infrared Photon-Counting Camera for High-Sensitivity Observations
- Magazine Article
- TBMG-12687
Language:
- English
Topic:
The dark current of a transferred-electron photocathode with an InGaAs absorber, responsive over the 0.9-to-1.7-μm range, must be reduced to an ultralow level suitable for low signal spectral astrophysical measurements by lowering the temperature of the sensor incorporating the cathode. However, photocathode quantum efficiency (QE) is known to reduce to zero at such low temperatures. Moreover, it has not been demonstrated that the target dark current can be reached at any temperature using existing photocathodes.