The f-sum rule, relating effective masses to oscillator strengths, is extended to semiconducting superlattices and applied to GaAs-(Ga,Al)As and HgTe-CdTe. This novel approach is implemented analytically by use of the envelope-function approximation to calculate both parallel and perpendicular masses and is used to account for their difference physically. Agreement with experiment is excellent, but in HgTe-CdTe only if the valence-band offset is small.
ASJC Scopus subject areas
- Physics and Astronomy(all)