Theory of Nested d-p Model with Strong Repulsion

Abstract

The nested d-P model with a strong repulsion on d-sites is studied. Starting with Green functions of a normal paramagnetic state in an isolated atomic limit (transfer->0), expansions with respect to residual interactions are performed and scaling equations are solved. The attraction between d-electrons mediated by doped holes plays a dominant role. The possible orders in one­ dimension are of charge-density wave and singlet superconductivity for small doping, and of charge and spin-density wave for large doping, respectively. In quasi-one-dimension only charge-density wave establishes three-dimensional order and the fluctuation of singlet superconductivity develops in short range.