Physical Sciences and Mathematics Commons^™

Infrared Spectral Detectivity Of Cr‐Doped Gaas, David C. Look

Physics Faculty Publications

The room‐temperature spectral detectivity of Cr‐doped GaAs has been examined in the impurity excitation region out to 1.7 μ, a range which includes the wavelengths of several important lasers as well as low‐loss optical fibers. The results include values of D∗ greater than 10¹¹ cm Hz^1/2/W in the photoconductive mode, and 10¹⁰ cm Hz^1/2/W in the photomagnetoelectric mode. Small carrier lifetimes, ∼10⁻⁸ sec, offer the potential of high‐speed operation; however, the measured response times are much larger, ∼10⁻³–10⁻² sec, because of very high input impedances. Formulas are presented to …