Band structure and interband optical transitions in the sawtooth superlattice.

Abstract

The band structure and interband matrix elements of the ${\mathrm{Al}}_{\mathrm{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$As sawtooth superlattice are analyzed. We have shown that the envelope wave functions may be expressed as integrals of elementary functions. Numerical results are given for a superlattice with maximal mole fraction ${x}_{\mathrm{max}}$=0.3, and period equal to 14 nm. A comparison of our results with those obtained via the pseudopotential method is given. Also, the possibility of determining the conduction-band offset \ensuremath{\Delta}${E}_{c}$ from optical measurements, based on strong dependence of the transition matrix elements on \ensuremath{\Delta}${E}_{c}$, is discussed.