Superlattice k⋅p models for calculating electronic structure

A quantitative comparison is presented of two realistic superlattice k⋅p electronic structure calculations. The first is an analytic approach based on an extended bulk Kane model; the second is an extended-basis treatment, developed by McGill and collaborators, based on bulk pseudopotential calculations. Both approaches are applied to HgTe/CdTe superlattices. Energies, wave functions, effective masses, and oscillator strengths are found to agree within 10%. The limited-basis approach based on the Kane model is seen to be adequate for superlattices whose bulk constituents have direct gaps in the conduction- and valence-band regions near the superlattice band gap.