Terahertz Radiation Driven Chiral Edge Currents in Graphene
Journal article, 2011
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.
semiconductors
ionization
deep impurities
epitaxial graphene
Author
J. Karch
C. Drexler
P. Olbrich
M. Fehrenbacher
M. Hirmer
M. M. Glazov
S. A. Tarasenko
E. L. Ivchenko
B. Birkner
J. Eroms
D. Weiss
R. Yakimova
Samuel Lara Avila
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Sergey Kubatkin
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
M. Ostler
T. Seyller
S. D. Ganichev
Physical Review Letters
0031-9007 (ISSN) 1079-7114 (eISSN)
Vol. 107 27New Electronics Concept: Wafer-Scale Epitaxial Graphene (ConceptGraphene)
European Commission (EC) (EC/FP7/257829), 2010-10-01 -- 2013-09-30.
Subject Categories
Physical Sciences
DOI
10.1103/PhysRevLett.107.276601