N-color (hg,cd)te photodetectors.

N-color (Hg,Cd)Te photodetectors capable of spectral band analysis have been fabricated, tested, and delivered. This paper discusses the state of the art in (Hg,Cd)Te n-color photoconductive detectors. Included is a discussion of narrow band two-color devices responsive in the region of 8-14 micro. D*lambda (lambda(p), 10 kHz, 1) higher than 3.5 x 10(9) cm Hz((1/2))/W have been achieved in both top and bottom elements at 95 K. The top element exhibited a cutoff wavelength of 8.8 micro, while the bottom element was responsive from 9.6 micro to 11.1 micro. The device was assembled with a long-wavelength pass filter that yielded two narrow bands. Preliminary results are also included for a unique three-color (Hg,Cd) Te device with cutoff wavelengths of 9.1 micro, 10.8 micro, and 13.8 micro.