Photoemission study of an f-electron superconductor: CeRu2

Photoemission study has been performed for a high-quality single crystal of CeRu2, including resonant photoemission near the Ce 4d-->4f absorption edg e and high-resolution photoemission at a low-photon energy. Resonant photoe mission study provides evidence for the large hybridization between Ce 4f a nd conduction electrons, indicating mixed-valence in CeRu2. It is found tha t the line shape of the high-resolution spectrum near the Fermi level depen ds on the experimental conditions and the sample surface treatment. Compari son of photoemission data to the calculated density of states reveals that band calculations provide a reasonably good description of the electronic s tructure of CeRu2. [S0163-1829(99)01831-7].