CPM Seminar

Graphene: Kinks, Superlattices, Landau levels, and Magnetotransport

Arun Paramekanti

Department of Physics
University of Toronto

Bilayer graphene is an interesting candidate for a semiconductor with an electric field tunable bandgap. We show that a sign reversal of the electric field leads to topologically confined one dimensional modes akin to domain wall fermions. These modes get converted into a tunable 2-band Luttinger liquid in the presence of interactions, with observable consequences for tunneling and transport. Coupling many such kink states leads to a superlattice which supports new linearly dispersing Dirac fermion modes. We also study superlattices and magnetotransport in monolayer and bilayer graphene, again finding evidence for generation of new Dirac fermion modes. In monolayer graphene, we find that a moderate magnetic field leads to a reversal of the transport anisotropy imposed by the superlattice due to the dispersion of the zeroth Landau level, an effect which may find possible applications.