Nature of Doped Electrons in Nd_2-xCe_xCuO₄. II.Electronic Band Structures of Nd₂CuO₄Type LaThCuO₄

Abstract

The APW band calculations for LaThCuO 4 with Nd 2 CuO 4 type crystal structure were performed with two kinds of structure for the La and Th layers. It was shown that, as the Th doping increases in La 2 CuO 4 , the Cu d -O p antibonding band on the CuO 2 layer rises steadily but the La-Th d ( xy ) band falls sharply with the bottom at the X point. In LaThCuO 4 , the bottom of d ( xy ) band is well below the top of the antibonding band as well as the Fermi energy. Various experimental results in the Th or Ce doped Nd 2 CuO 4 are explained by the present result.