Influence of Spatial Correlations in Strongly Correlated Electron Systems : Extension to Dynamical Mean Field Approximation(Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties)

概要

論文の詳細を見る
We propose a formalism to take account of the correction of the spatial fluctuations to the local selfenergy obtained by the dynamical mean-field approximation. For this purpose, the approximate dynamical susceptibility in the framework of the iterated perturbation theory is proposed and examined. Using the formalism, it is demonstrated that the one-particle spectral intensity in the two-dimensional Hubbard model at half-filling exhibits the pseudo-gap behavior in the central coherent quasiparticle peak due to the critical antiferromagnetic fluctuation. The specific heat is considerably enhanced by the shortrange order, which assists a tendency of the Mott localization showing the reduction of the double occupancy. We briefly discuss a formulation for the superconducting transition temperature in the present approximation.
社団法人日本物理学会の論文
2006-05-15