| AVS 57th International Symposium & Exhibition | |
| Graphene Focus Topic | Thursday Sessions |
| Session GR+AS+TF+MI-ThA |
| Session: | Graphene: Surface Characterization |
| Presenter: | R.T. Decker, University of California Berkeley |
| Authors: | R.T. Decker, University of California Berkeley V.W. Brar, University of California Berkeley M.H. Solowan, University of California Berkeley Y.C. Wang, University of California Berkeley A. Zettl, University of California Berkeley M.F. Crommie, University of California Berkeley |
| Correspondent: | Click to Email |
Understanding the scattering properties of electrons in graphene is important for controlling the behavior of different graphene nanostructure-based devices. Here we report a scanning tunneling microscopy (STM) and spectroscopy (STS) study of impurities on a single monolayer of graphene. In our experiments the graphene is placed on a layer of insulating SiO2 that sits above a doped silicon back-gate electrode. We will discuss our observations of the electronic local density of states of impurities, as well as how these properties respond to electrical gating of the graphene monolayer with respect to the silicon back-gate electrode.
In particular, we will show that the combination of the back-gate voltage and the STM tip-gating effect allows the controlled ionization of the impurity when the resonance sweeps through the Fermi energy. The influence of this induced Coulomb potential on the electrons in graphene in the vicinity of the impurity will be discussed.