Functionalization of Graphene Nanostructures

Patterning of graphene into narrow stripes leads to exciting alterations of the extraordinary band structure of graphene. For instance, the electronic confinement in these so called graphene nanoribbons (GNR) gives rise to topologically protected edge states depending on the edge orientation and the crystal quality.

GNR are epitaxially grown on nanofacets of SiC mesa structures to avoid any damages of post-processing. The local transport properties as well as the electronic structure of as-grown GNR are studied by means of a 4-tip STM, which allows to perform transport measurements with probe spacings smaller than 100 nm.

We have shown that the nanoribbons produced with that method exhibit an extraordinary quality resulting in exceptional transport properties. Moreover, our results indicate a fully spin-polarized single channel ballistic transport behavior. Finally, the major objective of my studies is to explore the origin of this unique transport channel as well as the functionalization of GNR by adsorption of magnetic and non-magnetic impurities.

Jens Baringhaus, Mikkel Settnes, Johannes Aprojanz, Stephen R. Power, Antti-Pekka Jauho, and Christoph Tegenkamp: Electron Interference in Ballistic Graphene Nanoconstrictions, Phys. Rev. Lett. 116, 186602 (2016)

J. Baringhaus, J. Aprojanz, J. Wiegand, D. Laube, M. Halbauer, J. Hübner, M. Oestreich and C. Tegenkamp: Growth and characterization of sidewall graphene nanoribbons, Appl. Phys. Lett. 106, 043109 (2015)

Jens Baringhaus, Ming Ruan, Frederik Edler, Antonio Tejeda, Muriel Sicot, Amina Taleb-Ibrahimi, An-Ping Li, Zhigang Jiang, Edward H. Conrad, Claire Berger, Christoph Tegenkamp, Walt A. de Heer: Exceptional ballistic transport in epitaxial graphene nanoribbons , Nature, 506, 349 (2014)