▎ 摘　　要

Photoluminescence spectroscopy (PL) and angle resolved photoemission spectroscopy have been used to study the interaction between epitaxially grown graphene and the silicon carbide (SiC) substrate. We report evidence of an anomalous temperature dependent shift in the Fermi energy with a maximum at 65 K. A similarly anomalous onset of the photoluminescence spectrum is also observed at this temperature. These results are explained by the formation of a Schottky barrier at the graphene/SiC interface, which is also responsible for large electron doping of epitaxially grown graphene films. Moreover, we identify a strong resonance between the sharp no-phonon peaks of the D(1) photoluminescence spectrum in SiC and the electronic transition across the barrier, suggesting that epitaxial graphene might be also used to selectively detect photons of precise energies.