The electronic structure of high-Tc superconductors and related materials is studied by photoemission spectroscopy and Bremsstrahlung Isochromat spectroscopy. In the solid solution (La,Sr)2CuO4, (Nd,Ce)2CuO4, and (La,Sr)2NiO4 systems, the valence band spectra do not shift as a function of the doping concentration, which suggests that EF is pinned by the states within the charge-transfer gap and that the rigid band description is not appropriate in considering the metal-insulator transition in these systems.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering