Author/Authors :
Takahashi، نويسنده , , Toru and Sugawara، نويسنده , , Katsuaki and Noguchi، نويسنده , , Eiichi and Sato، نويسنده , , Takafumi and Takahashi، نويسنده , , Takashi، نويسنده ,
Abstract :
We have performed high-resolution angle-resolved photoemission spectroscopy of oxygen-adsorbed monolayer graphene grown on 6H–SiC(0 0 0 1). We found that the energy gap between the π and π∗ bands gradually increases with oxygen adsorption to as high as 0.45 eV at the 2000 L oxygen exposure. A systematic shrinkage of the π∗ electron Fermi surface was also observed. The present result strongly suggests that the oxidization is a useful technique to create and control the band gap in monolayer graphene.