Band Gap of Disordered Binary Alloys with Off-Diagonal Disorder —Repulsive Effect between Bands—

Abstract

The band gap of disordered binary alloys due to off-diagonal disorder is investigated quantitatively in the tight-binding model. The numerical results based on the Blackman et al. theory show that the shape of the density of states as well as the band edges are strongly affected by the repulsive effect between bands caused by the inter-band interaction. It is also shown that the effect is prominent even when the bands of component pure metals overlap.