Studies of the Electronic and the Optical Properties of the Ordered Ternary Alloys X0.5Y0.5O2(X, Y=Si, Ge, Sn) by Using First-principles Calculations

摘要

In this paper, the electronic and the optical properties of oxides for group-IV elements in an inverse Ag2O structure, including Si, Ge, and Sn, and their ternary alloys, were studied with the density function theory of first principles. The results show that they have a high-density phase and a high dielectric constant. Moreover, the lattice constants of Sio.5Geo.5O2 and SiC>2 are really close to those of Si(100) surfaces, suggesting the possibility of forming a defect-free superlattice. With changing element, the calculated results show that the lattice constants of the ternary alloys tend to be bigger while the energy gaps show a different trend. The optical properties of these compounds as functions of physical quantities, such as the density of states, the complex dielectric function, and the static dielectric constant, are given to support the potential applications of the compounds hi the future.