Origin of energy gap of graphene grown on Hex Au(001) substrate

Terasawa, Tomoo   ; Yasuda, Satoshi   ; Matsunaga, Kazuya*; Hayashi, Naoki*; Tanaka, Shinichiro*; Norimatsu, Wataru*; Ito, Takahiro*; Machida, Shinichi*; Asaoka, Hidehito  

Graphene grown on Hex-Au(001) substrate shows an energy gap in its -band. Previous reports speculated that the periodic potential of Hex-Au(001) resulted in the energy gap formation in the -band of graphene. In the present study, we found by angle-resolved photoemission spectroscopy that the hybridyzation of sp-band of Hex-Au(001) and -band of graphene created the energy gap in the -band of graphene.