Electronic structure of the quaternary alloy GaxIn1−xAsyP1−y

A method for calculating the electronic structure of the quaternary alloy GaxIn1−xAsyP1−y is presented. We have used the empirical pseudopotential method coupled with the virtual crystal approximation, which incorporates the compositional disorder as an effective potential. The electronic structure are studied for GaxIn1−xAsyP1−x (x = 0.5; y= 0.5) and GaxIn1−xAsyP1−y lattice matched to InP as well as GaAs. Good agreement with experiment is obtained for the calculated values of the direct energy gap and the bowing parameter at the λ point of the InP-lattice-matched quaternary alloy.