Surface effects on the electronic properties of YBa2Cu3O7

We present the results of a theoretical study of the modifications induced by the surface on the electronic structure of YBa2Cu3O7. Basal plane surfaces terminated with Ba and with Cu-O planes are considered. The calculated local densities of states show that the main structures of the bulk density of states may be drastically modified, specially near the Fermi energy, and new surface derived features appear in the spectrum. Significant changes occur also in the occupancies of the atoms near the surface.