Pseudospin-electron model spectrum in alloy analogy approximation

• Main Authors: I.V.Stasyuk, V.O.Krasnov
• Format: Article
• Language: English
• Published: Institute for Condensed Matter Physics 2006-01-01
• Series: Condensed Matter Physics
• Subjects: dynamical mean-filed theory; irreducible Green's functions; pseudospin-electron model; alloy analogy approximation
• Online Access: http://dx.doi.org/10.5488/CMP.9.4.725

Energy spectrum of the pseudospin-electron model is investigated in the alloy analogy approximation within the framework of the dynamical mean field theory (DMFT). The case of two near Hubbard-like electron subbands, which determine the location of chemical potential at a certain set of model parameter values, is considered. The conditions of gap appearance in the spectrum are established. The effect of the asymmetry field h and tunneling-like splitting of levels in the local anharmonic well on the critical value U_crit of the on-site Hubbard interaction constant is investigated.