Phase diagram of La2-xMxCuO4 as the key to understanding the nature of high-Tc superconductors

Results of high-T-c superconductivity studies are analyzed using the authors' model, which assumes that the interaction of electrons with two-site negative-U centers (due to charged dopant localization near impurity ions) is responsible for many anomalous properties, and indeed the very superconductivity, of high-T-c superconductors. It is shown that the basic properties of high-T-c superconductors and the details of the superconducting and magnetic phase diagrams of La2-xMxCuO4 (M = Ba, Sr) can be explained by this model.