English

Spectral Properties of the Generalized Spin-Fermion Models

Strongly Correlated Electrons 2009-11-07 v1 Superconductivity

Abstract

In order to account for competition and interplay of localized and itinerant magnetic behaviour in correlated many body systems with complex spectra the various types of spin-fermion models have been considered in the context of the Irreducible Green's Functions (IGF) approach. Examples are generalized d-f model and Kondo-Heisenberg model. The calculations of the quasiparticle excitation spectra with damping for these models has been performed in the framework of the equation- of-motion method for two-time temperature Green's Functions within a non-perturbative approach. A unified scheme for the construction of Generalized Mean Fields (elastic scattering corrections) and self-energy (inelastic scattering) in terms of the Dyson equation has been generalized in order to include the presence of the two interacting subsystems of localized spins and itinerant electrons. A general procedure is given to obtain the quasiparticle damping in a self-consistent way. This approach gives the complete and compact description of quasiparticles and show the flexibility and richness of the generalized spin-fermion model concept.

Keywords

Cite

@article{arxiv.cond-mat/0208227,
  title  = {Spectral Properties of the Generalized Spin-Fermion Models},
  author = {A. L. Kuzemsky},
  journal= {arXiv preprint arXiv:cond-mat/0208227},
  year   = {2009}
}

Comments

37 pages, Latex