We present a method which allows the self-consistent treatment of short-range order in the construction of the single-particle Greens function for substitutionally disordered alloys. In this method, the electronic self-energy is determined through the condition that the scattering off the center of a cluster of atoms vanishes upon averaging over all cluster configurations. While this method leads to an effective medium which is only slightly more accurate than that obtained in the single-site coherent potential approximation, it provides by contrast quite an appropriate medium to be used in conjunction with the embedded cluster method (ECM). Comparison with the results of exact numerical simulations shows that an application of the ECM to rather small clusters leads to accurate representations of the density of states of nonrandom substitutionally disordered alloys. Several possible applications of the method are discussed.
ASJC Scopus subject areas
- Condensed Matter Physics