Generalized augmented-space theorem for correlated disorder and the cluster-coherent-potential approximation

Theory of electronic transport in random alloys with short-range order: Korringa-Kohn-Rostoker nonlocal coherent potential approximation

“…Mookerjee and co-workers, 27-29 using a tight-binding, linear muffin tin orbitals ͑TB-LMTO͒ method 30 in conjunction with an augmented space formalism 31,32 and real space recursion method, 33 described SRO effects on alloy electronic densities of states and related quantities, while Saha et al 34 obtained spectral functions within the same framework. Recently, Tarafder et al 35 developed a formalism for the optical conductivity and reflectivity from the same basis and used it to study copper-zinc alloys.…”

Augmented space recursion study of the effect of disorder on superconductivity

“…We can use the generalized augmented space method introduced by Mookerjee and Prasad. 31 The method has been described in great detail in Ref. 31 and here we shall introduce only those essential ideas which are necessary for our exposition.…”

“…The construction of that operator has been discussed in detail in the earlier paper. 31 We can characterize short-ranged order by a Warren-Cowley parameter ␣͑R͒ =1 − P AB ͑R͒ / x, where x is the concentration of an A type of atom and P AB ͑R͒ is the probability of finding a B atom at a distance R from an A atom. Using this ␣, the conditional probabilities are given by the following.…”

Short-range order and its effect on the electronic structure of binary alloys: CuZn — a case study

“…The problem with these approaches was that they became intractable as the size of the cluster was increased much beyond two sites. Mookerjee and Prasad [48] generalized the augmented space theorem to include correlated disorder. However, since they then went on to apply it in the CCPA approximation, they could not go beyond the two-site cluster and they applied the method to model systems alone.…”

“…The generalized augmented space theorem has been described in detail by Mookerjee and Prasad [48]. Let us briefly introduce those essential ideas which are necessary to make this communication reasonably self-contained.…”