Speaker: Jan Bundesmann (University of Regensburg)
Title: Spin conductance of diffusive graphene nanoribbons
Date/Time: Nov 21st, Wednesday @ 14:40-15:30
Place: Sabanci University, SUNUM building, room G111
Graphene, when cut along a zigzag edge, shows a strongly increased density of states at energies close to the charge neutrality point. The electron states that are the source of this increased DOS are pseudospin-polarized, i.e. they occupy mainly one sublattice, while their wavefunction decays exponentially from the zigzag edge. In such systems one expects magnetic ordering which manifests as an antiferromagnetic alignment of the two sublattices. Due to the pseudospin polarization of the low-energy states, finite local magnetic moments appear along the edges. We investigate how the formation of these local magnetic moments influences charge and spin transport in graphene. We show how this can lead to a finite spin conductance of a single graphene nanoribbon. Moreover, within the localized transport regime, the spin conductance fluctuations exhibit universal behaviour in the sense that they don't depend on the exact modelling of the magnetization. Strikingly, even a large amount of edge roughness does not lead to deviations from this universal behaviour.
contact: Inanc Adagideli, firstname.lastname@example.org