BOF NI project: Interplay between atomic layers and functional adsorbates (R-3653)

Graphene is a non-magnetic, two-dimensional semimetal, which can be turned into an n- or p-type conductor by gate voltages. This results in unusually high charge carrier mobilities with mean free paths of several microns. The carriers follow a linear dispersion relation where the energy is proportional to the wave number, a behavior that is expected for massless particles. Within this project, we consider graphene in an electronic- and magnetic sense as a 'blank page', which will be modified by introducing defects, by adsorbed/implanted gas- or metal atoms, and by covalently bound atoms and chemical groups. We will monitor the evolution of the band-structure related, electronic and magnetic properties as a function of the type and density of these modifications. Hereby, theoretical modeling based on ab initio calculations and experimental analyses (conductivity, scanning probe microscopy in various forms, photocurrent spectroscopy) will go hand in hand. Special emphasis goes to the quest whether it is possible to achieve an 'engineered' band gap via targeted modifications: this would open broad applications from nanoelectronics to (bio-)chemical sensors. Analysis of deliberately induced defects includes also the mutual ordering of defects and the orientational ordering of adsorbants with respect to the underlying graphene layer.

Keywords:wide band gap materials

Disciplines:Physical sciences, Chemical sciences, Biological sciences, Materials engineering, Basic sciences, Clinical sciences, Translational sciences