Magneto-optical studies of strained PbTe

Interband magneto-optical studies are reported on strained and unstrained films of PbTe grown on BaF 2 , NaCl and PbTe substrates. By a careful orientational study of the magneto-absorption of these films it has been possible to deduce an accurate set of band parameters for PbTe, using the six-band Mitchell-Wallis k.p model. It is demonstrated that the inbuilt strain in the layers is an important parameter, which can cause changes in both the bandgap, and the momentum matrix element coupling the L 3- 6- and L 1+ 6+ bands. Both uniaxial and hydrostatic components of strain are shown to be present, and these are used to deduce the deformation potentials for PbTe. The anisotropy of the conduction and valence bands is shown to be independent of the strain.