Effect of local order on the electronic states of binary alloys

Abstract

The Green function technique of Edwards (1962) is used to obtain the energy spectrum and density of states for an electron moving in a binary alloy with local order, that is, with a non random distribution of A and B atoms. The model consists of an electron with an effective mass, perturbed by a potential which fluctuates from site to site and has zero average value. The degree of local order in this fluctuating potential is expressed approximately in terms of a single parameter alpha . Calculations for a 50-50 alloy show that the reciprocal lifetime changes greatly as alpha moves from negative (anticlustering) through zero (random) to positive values (clustering). This change should be observable in resistance measurements.