Configuration averaged spin correlation functions using the generalized recursion in augmented space : application to FeCr, FeMn and FeCo alloys

The focus of this communication is twofold : First, to introduce a methodology which seamlessly combines three approaches : the density functional based linear muffin-tin orbitals for self- consistently obtaining a sparse Hamiltonian; the generalized recursion method to obtain the one and two-particle Green functions and augmented space approach to deal with disorder averaging. The same formalism applied to both spectral and response properties should make the errors compatible in different studies. The underlying computational routines are fast, parallelize and made easy to handle. Secondly, to demonstrate a successful application to three sets of alloys FeCo,FeCr,FeMn with increasing disorder concentration (x) . We discuss that our method has sufficient generality to encompass those features which are at present absent from our simplified model.This method captures a significant magnon softening for disordered FeCo alloys and spin-glass like (SGL) behaviour of disordered FeCr and FeMn alloys.