CENTRAL EUROPEAN JOURNAL OF PHYSICS, vol.11, no.12, pp.1680-1685, 2013 (SCI-Expanded)
Using the first-principles band-structure method, we have calculated the structural and electronic properties of zincblende TlAs, TlP, GaAs and GaP compounds and their new semiconductor Tl (x) Ga1-x As (y) P1-y quaternary alloys. Structural properties of these semiconductors are obtained with the Perdew and Wang local-density approximation. The lattice constants of Tl (x) Ga1-x As, Tl (x) Ga1-x P ternary and Tl (x) Ga1-x As (y) P1-y quaternary alloys were composed by Vegard's law. Our investigation on the effect of the doping (Thallium and Arsenic) on lattice constants and band gap shows a non-linear dependence for Tl (x) Ga1-x As (y) P1-y quaternary alloys. The band gap of Tl (x) Ga1-x As (y) P1-y , E (g) (x, y) concerned by the compositions x and y. To our awareness, there is no theoretical survey on Tl (x) Ga1-x As (y) P1-y quaternary alloys and needs experimental verification.