Project Details
Projekt
Tailoring the electronic structure of epitaxial graphene on SiC
Applicant
Dr. Kathrin Küster
Subject Area
Experimental Condensed Matter Physics
Term
since 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 449119662
Graphene, a two-dimensional layer of hexagonally arranged carbon atoms, is one of the most interesting materials today, due to its outstanding mechanical and electronic properties. However, for possible implementation in devices it is essential to steer its electronic characteristics. Functionalization by means of proximity coupling is a promising way to modify the electronic properties while maintaining the structural integrity. Silicon carbide (SiC) - a wide band gap semiconductor - is one of the most versatile platforms to investigate graphene since wafer-sized graphene layers can be grown via sublimation and direct implementation into device fabrication is feasible. Intercalation of atomic species between the SiC and the graphene is a widely used method to modify graphene’s properties. By this technique, not only the doping of graphene can be precisely tuned but also otherwise unstable 2D materials can be stabilized at the graphene/SiC interface, which might exhibit very different properties compared to their 3D counterparts. In this project, which is part of the research unit, we want to use intercalation and on surface functionalization to deliberately modify the electronic properties of graphene via proximity coupling. By the intercalation of materials that show a giant Rashba effect, it is anticipated to induce spin splitting into graphene’s π-bands, which is a prerequisite to implement graphene into spintronics. The combination of the mass-less Dirac electrons of graphene with the flat bands in heavy Fermion materials will lead to artificial Lieb-lattices. It is expected that highly correlated states like spin, or charge density waves or superconductivity emerge. By starting with two carbon layers on SiC, so-called monolayer graphene and intercalation of lanthanides – which are known to induce heavy electron doping – between SiC and graphene as well as in the graphene galleries new levels of complexity will be explored. Although intercalation is a widely used method for functionalizing the properties of graphene, the exact mechanism and the influence of defects on the intercalation paths are not well understood. Therefore, we want to explore the intercalation in graphene layers that exhibit different amounts and types (point defects, line defects, …) of defects, which will also help to improve intercalation recipes for the future.
DFG Programme
Research Units
