Talk given by Prof. Ferdinand Evers, Universität Regensburg Abstract: Carbon based matter and its electronic properties is a research topic that includes an enormous amount of different and sometimes surprising facets. A well known example is graphene with its relativistic band structure, exhibiting two Dirac-cones. The talk will offer an overview about new theoretical predictions that reveal other peculiar electronic properties of carbon based matter. For instance, when dressing graphene with adsorbates, such as hydrogen, the cusp in the density of states can give way to a singular peak under certain conditions. An electrical current flowing through this system exhibits eddies (current vortices) that can be associated with magnetic fields reaching hundreds of milliTesla per Volt. When decreasing the sheet size and forming (clean) graphene nano-ribbons, the current flows along narrow streamlines that are separated by regions of zero flow. Finally, when chopping a very narrow zigzag-ribbon into molecules (oligoacenes), excitation gaps appear that oscillate with the molecular length with an incommensurate period of the order of ten rings. Literature: V. Häfner,J. Schindler, N. Weik, T. Mayer, S. Balakrishnan, R. Narayanan, S. Bera, FE, to appear in Phys. Rev. Lett. (2014). M. Walz, J. Wilhelm, FE, Phys. Rev. Lett. 13, 136602 (2014). J. Wilhelm, M. Walz, FE, Phys. Rev. B 89, 195406 (2014). R. Korytár, D. Xenioti, P, Schmitteckert, M. Alouani, FE, to appear in Nature Communications (2014).

This event is part of the eventgroup INT Talks

Homepage
https://www.int.kit.edu/events.php

Speaker
Prof. Ferdinand Evers, Universität Regensburg

Universität Regensburg

Organizer
Dr. Matthias Hettler
Institut für Nanotechnologie
KIT
Karlsruhe
Mail: matthias hettler ∂does-not-exist.kit edu
https://www.int.kit.edu

Targetgroup
Interested / Everyone