Charge ordering, superconductivity, and stripes in doped La2CuO4

Abstract

The special features of the phase diagrams of La2−x SrxCuO4 are considered in terms of the high-temperature superconductivity model according to which the mechanism responsible for the anomalous properties of these compounds is the interaction of electrons with diatomic negative U-centers. A microstructural model that assumes the coexistence of domains with different types of dopant ion ordering is suggested for La2−x SrxCuO4. According to this model, the main characteristics of the experimental phase diagrams of La2−x SrxCuO4 only reflect square lattice geometric relations and competition between different dopant ordering types. Close agreement between the calculated and experimental “superconducting” and “magnetic” phase diagrams is an important argument in favor of the suggested high-temperature superconductivity model.