Absence of orbital-dependent Mott transition in _x

Institut für Festkörperforschung, Forschungszentrum Jülich - 52425 Jülich, Germany

Received: 31 January 2003
Accepted: 6 May 2003

Abstract

The Mott transition between the metallic and insulating paramagnetic phases of the layer perovskite _x is analyzed within the Dynamical Mean Field Theory. To simulate the band narrowing caused by finite doping concentrations, quasi-particle spectra appropriate for are evaluated for increasing values of the on-site Coulomb energy U. At small U the planar geometry splits the bands near into a wide, two-dimensional d_xy band and two narrow, nearly one-dimensional bands. At larger U, however, the spectral distribution of these states exhibits similar correlation features, suggesting a common metal-insulator transition for all bands at the same critical U.