Effect of deformation on the conduction band of III-V semiconductors

We develop a theory describing the effect of mechanical deformation on the conduction-band eigenstates in the vicinity of the $\Gamma$ point in the III-V semiconductors. In this theory all strain-induced effects are interpreted in terms of the admixture of $s$- and $p$-like states used to describe the conduction band for zero deformation. Unlike previous work, the results can be applied regardless of the relative size of the band gap $E_g$ and spin-orbit splitting $\Delta$. A previously neglected term in the part of the Hamiltonian describing the effect of deformation is found to produce substantial contributions for sufficiently large energies above the band edge. Both of these aspects are particularly important when the narrow-gap materials like InSb are considered. Our theory is also the first to predict the magnitude of the splitting of the conduction-band degeneracy for deformations of certain symmetry.