This paper discusses the validity of the band picture in high-Tc superconductors on the basis of rigorus spectroscopic results for a Cu4O8 cluster. The calculated single particle spectra at low energies are qualitatively consistent with the band model. However, a large energy gap appears in the undoped ground state where a four-spin interaction is found to be important.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering