BAND-POPULATION EFFECTS AND INTRABAND MAGNETO-OPTICAL PROPERTIES OF A MANY-VALLEY SEMICONDUCTOR - PBTE

We have performed magnetoreflectivity experiments on n-PbTe epitaxial films using the Faraday configuration (B[111]) in the frequency range of 10-400 cm-1 and in magnetic fields up to 14 T. Cyclotron-resonance structures and dielectric anomalies have been observed at frequencies between the TO and LO lattice modes of PbTe. We interpret our results using a free-carrier susceptibility derived within the framework of a linear-response theory. The Landau-level structure has been calculated according to the kp approach of Mitchell and Wallis. In the quantitative description of magnetoreflectivity spectra we take into account the magnetic-field-dependent occupation of the Landau states. Fitting our data we determine a set of band parameters for PbTe, which also successfully describe magneto-optical experiments of other authors. © 1979 The American Physical Society.