Karch, Johannes and Drexler, Christoph and Olbrich, Peter and Fehrenbacher, M. and Hirmer, M. and Glazov, M. M. and Tarasenko, Sergey and Ivchenko, Eougenious and Birkner, Bastian and Eroms, Jonathan and Weiss, Dieter and Yakimova, R. and Lara-Avila, S. and Kubatkin, S. and Ostler, M. and Seyller, T. and Ganichev, Sergey (2011) Terahertz Radiation Driven Chiral Edge Currents in Graphene. Physical Review Letters (PRL) 107, p. 276601.
We observe photocurrents induced in single-layer graphene samples by illumination of the graphene edges with circularly polarized terahertz radiation at normal incidence. The photocurrent flows along the sample edges and forms a vortex. Its winding direction reverses by switching the light helicity from left to right handed. We demonstrate that the photocurrent stems from the sample edges, which reduce the spatial symmetry and result in an asymmetric scattering of carriers driven by the radiation electric field. The developed theory based on Boltzmann’s kinetic equation is in a good agreement with the experiment. We show that the edge photocurrents can be applied for determination of the conductivity type and the momentum scattering time of the charge carriers in the graphene edge vicinity.
|Date:||27 December 2011|
|Institutions:|| Physics > Institute of Experimental and Applied Physics > Professor Ganichev > Group Sergey Ganichev|
Physics > Institute of Experimental and Applied Physics > Chair Professor Lupton > Group John Lupton
Physics > Institute of Experimental and Applied Physics > Chair Professor Weiss > Group Dieter Weiss
|Projects:||GRK 1570, Elektronische Eigenschaften von Nanostrukturen auf Kohlenstoff-Basis|
|Subjects:||500 Science > 530 Physics|
|Refereed:||Yes, this version has been refereed|
|Created at the University of Regensburg:||Yes|
|Deposited On:||28 Feb 2012 08:34|
|Last Modified:||28 Feb 2012 08:34|