Effects of crystal ordering and composition on properties of CdSxTe1−x alloys: a first-principle insight

Abstract

Effects of crystal ordering and composition on the properties of CdSxTe1−x alloys are studied using first-principle calculations. The authors find that the chalcopyrite structure with (201) ordering has the lowest formation energy. (110) Y2 ordering can occur in disordered structure due to the small energy difference. The authors find that the spin-orbit (SO) splitting, band gap and their bowing parameters are significantly dependent on the ordering and composition. For the compound CdS0·5Te0·5, negative bowing parameter of SO splitting is found in ordered structures, while positive bowing parameter is found in disordered structure. For a given (100) ordering, the bowing parameter of energy gap increases with the decreasing of the bowing parameter of SO splitting.