Tuning the interlayer coupling of the twisted bilayer graphene by molecular adsorption, J. Phys. Chem. C 2014, 118, 6462−6466
Lan Meng †, Wei Yan †, Longjing Yin †, Zhao-Dong Chu †, Yanfeng Zhang ‡, Lei Feng †, Ruifen Dou *†, and Jiacai Nie †
Abstract
We describe a facile method to modulate the local interlayer coupling by adsorption of single-molecule magnets (SMMs) onto twisted bilayer graphene and report the characterization of its electronic band structure using scanning tunneling microscopy and spectroscopy. Low-energy Van Hove singularities (VHSs) and superlattice Dirac cones, induced by the interlayer coupling and graphene-on-graphene moiré, respectively, are observed in the tunneling spectra. Our experiments demonstrate that the energy difference of the two VHSs, which reflects the magnitude of interlayer coupling, can be tuned by the local coverage density of molecular adsorption.
