Band gaps and charge distribution in quasi-binary (GaSb) (InAs) crystals

Pseudopotential investigation of energy band gaps and charge distribution in quasi-binary (GaSb)_1-x(InAs)_x crystals has been reported. To the best of our knowledge, there had been no reported theoretical work on these materials. In agreement with experiment, the quasi-binary crystals of interest showed a significant narrowing of the optical band gap compared to the conventional Ga_xIn_1-xAs_ySb_1-y quaternary alloys (with x = 1 - y). Moreover, the absorption at the optical gaps indicated that (GaSb)_1-x(InAs)_x is a direct Γ to Γ band-gap semiconductor within a whole range of the x composition. The information derived from the present study predicts that the band gaps cross very important technological spectral regions and could be useful for thermophotovoltaic applications. Received 30 August 2002 Published online 1st April 2003 RID="a" ID="a"Present address: Physics Department, University of M'sila, 28000 M'sila, Algeria e-mail: N_Bouarissa@yahoo.fr