First Principle Self-Consistent Pseudopotential Calculation on the Electronic Structure of (InAs) ₁ (GaAs) ₁ Superlattice

Abstract

The band structure of the (InAs)l (GaAs)l strained superlattice is calculated by the self-consistent pseudopotentid method. The results show that the (1nAs)l (GaAs)l is a direct-gap superlattice. With the local density approximation, the band gap calculated with the room-temperature iattice constants is 0.43eV1 and the corrected value is 0.91 eV, in agreement with experimental results. Because of the lattice mismatch between h A s .and GaAs layers, the threefold degenerate energy level at the top of valence band splits into two levels with a spacing of 0.29eV. The splitting of energy level is also estimated and explained using the effective-mass theory.

Effective-mass theory for InAs/GaAs strained coupled quantum dots

“…22,23 In our calculations, the effects due to the different effective masses of electrons and holes in different materials, and the coupling between HH and light hole ͑LH͒ are included. Presently, to our knowledge, there is no suitable theory for this problem.…”