Cloning the Dirac cones of bilayer graphene to the zone center by selenium adsorption

Abstract Dirac cones can foster extraordinary electronic effects, as exemplified by the case of graphene layers. Angle-resolved photoemission reveals that adsorption selenium (Se) vapor on bilayer creates a symmetric hybrid clone at zone center. A detailed analysis aided first-principles calculations shows adsorbed layer consists an ordered array Se 8 molecules. The uncovered cloning mechanism illustrates method to generate features scientific and technological interests gentle surface modification via van der Waals adsorption.