Synchrotron radiation photoemission spectrum study on K3C60 film

K3C60 single crystal film was prepared on the cleaved (111) surface of C-60 single crystal. Synchrotron radiation angle-resolved photoemission spectra were measured at normal emission with sample temperature at similar to 150 K. Up to four subpeaks of LUMO-derived band were observed. These sub-peaks exhibit distinct energy dispersions which resemble in general the theoretic al ones calculated for K3C60 at low temperature with the so-called one-dime nsional disordered structure. But there is targe deviation of experimental sub-band intervals from the theoretical values. This result is meaningful f or the studies of the physical properties of alkali-doped C-60 solids, e.g. the mechanism for superconductivity.