Terahertz Radiation Driven Chiral Edge Currents in Graphene
Artikel i vetenskaplig tidskrift, 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

Författare

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, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Sergey Kubatkin

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

M. Ostler

T. Seyller

S. D. Ganichev

Physical Review Letters

0031-9007 (ISSN) 1079-7114 (eISSN)

Vol. 107

Ämneskategorier

Fysik

DOI

10.1103/PhysRevLett.107.276601