RPA-CPA theory for magnetism in disordered Heisenberg binary systems with long range exchange integrals

Details RPA-CPA theory for magnetism in disordered Heisenberg binary systems with long range exchange integrals RPA-CPA theory for magnetism in disordered Heisenberg binary systems with long range exchange integrals

2002-02-07

arxiv.org/abs/cond-mat/0202125v2

Physics

Condensed Matter

Strongly Correlated Electrons

The tex file had a defect, a new package is provided (the figures are unchanged). Paper is submitted to PRB

Scientific paper

10.1103/PhysRevB.66.014410

We present a theory based on Green's function formalism to study magnetism in disordered Heisenberg systems with long range exchange integrals. Disordered Green's function are decoupled within Tyablicov scheme and solved with a CPA method. The CPA method is the extension of Blackmann-Esterling-Beck approach to system with environmental disorder term which uses cumulant summation of the single-site non crossing diagrams. The crucial point is that we are able to treat simultaneously and self-consistently the RPA and CPA loops. It is shown that the summation of s-scattering contribution can always be performed analytically. While the p,d,f .. contributions are difficult to handle in the case of long-range coupling. To overcome this difficulty we propose and provide a test of a simplified treatment of these terms. In the case of 3D disordered nearest-neighbor Heisenberg system, a good agreement between the simplified treatment and the full calculation is achieved. Our theory allows in particular to calculate the Curie temperature, the spectral functions and the temperature dependence of the magnetization of each constituant as a function of concentration of impurity. Additionally it is shown that a virtual crystal treatment fails even at low impurity concentration

Affiliated with

Also associated with

No associations

Rating

RPA-CPA theory for magnetism in disordered Heisenberg binary systems with long range exchange integrals does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with RPA-CPA theory for magnetism in disordered Heisenberg binary systems with long range exchange integrals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and RPA-CPA theory for magnetism in disordered Heisenberg binary systems with long range exchange integrals will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-648864