The Masses of Free Holes and Electrons in Tellurium

The transverse effective hole masses of tellurium samples with p = 1016 to 1018 cm−3 have been determined from Faraday rotation measurements at 10, 90, and 300 K. The comparison of the experimental values with the calculated Faraday masses enables to prove the validity of various band models for large k. The model presented by Bangert gives the best fit. Thus the strong temperature dependence of the hole mass determined from transport measurements by many authors is shown to be due to the nonparabolicity of the valence band. At higher temperatures (300 to 400 K) also the free electrons contribute to the Faraday effect. This rotation could be explained by Bangert's model, too.