Infrared optical absorption of Hg1-xCdxTe
Abstract
The absorption near the fundamental absorption edge of Hg1-xCdxTe was measured over the composition range 0.205⩽x⩽0.220 at temperatures from 80 to 300 K. The dispersion of the index of refraction of Hg1-xCdxTe was obtained from the interference pattern. It was found that the absorption tail obeys a modified Urbach's rule and is expressed by α=α0 exp[σ (E-E0)/(T+T0)] for 20⩽α (cm-1) ⩽1000. The fitting parameters α0, σ, T0, and E0 vary regularly with x. The expression is used to obtain the absorption coefficient and the temperature coefficient of the gap as a function of x and T. Evidence is presented to show that these parameters may be extrapolated to calculate the absorption beyond the measured composition range.
- Publication:
-
Journal of Applied Physics
- Pub Date:
- June 1979
- DOI:
- 10.1063/1.326421
- Bibcode:
- 1979JAP....50.4356F
- Keywords:
-
- 78.20.Dj;
- 78.30.Gt;
- 85.60.Gz;
- Photodetectors