TEMPERATURE-INDUCED INTRABAND TRANSITIONS IN THE N-TYPE HGTE/CDTE SUPERLATTICE - COMMENT

On the basis of magneto-optical measurements on a HgTe-CdTe superlattice, Choi et al. [Phys. Rev. B 41, 10872 (1990)] have argued that the valence-band offset must be on the order of 40 meV. We show that rather than representing cyclotron resonance by electrons in the interior of the superlattice, the minima in their magnetotransmission spectra are more readily interpreted in terms of quasi-two-dimensional electrons residing near the interface of the superlattice with the substrate. When nonparabolicity is taken into account, the data are consistent with the large body of evidence favoring a large valence-band offset in this system.