S. Krishnamurthy et al., ELECTRONIC-STRUCTURE, ABSORPTION-COEFFICIENT, AND AUGER RATE IN HGCDTE AND THALLIUM-BASED ALLOYS, Journal of electronic materials, 26(6), 1997, pp. 571-577
The band structures, absorption coefficients, and Auger recombination
rates in narrow-gap alloys HgCdTe, InTlP, InTlAs, and InTlSb in the zi
nc blende structure, along with those of GaAs, are calculated using a
hybrid pseudopotential and tight-binding method. The composition-depen
dent band gaps of the thallium-based alloys are reported along with th
ose of several other semiconductor alloys. Within 50 meV from the abso
rption edge, the absorption coefficient of InxTl1-xP is found to have
about the same magnitude as that of HgxCd1-xTe and GaAs, while that of
InxTl1-xAs and InxTl1-xSb is much smaller. In agreement with previous
theories, the calculated Auger lifetimes in Hg0.78Cd0.22Te with unit
or k.p overlap agree very well with experiments. Among the thallium al
loys studied, the Auger lifetimes are longest in In0.33Tl0.67P, but st
ill shorter than those in Hg0.78Cd0.22Te by an order of magnitude. In
addition, realistic overlaps produce lifetimes one to two orders of ma
gnitude larger than those observed.