Terahertz Radiation Driven Chiral Edge Currents in Graphene
2011 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 107, no 27, 276601-1-276601-5 p.Article in journal (Refereed) Published
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.
Place, publisher, year, edition, pages
American Physical Society , 2011. Vol. 107, no 27, 276601-1-276601-5 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-73582DOI: 10.1103/PhysRevLett.107.276601ISI: 000298609900010OAI: oai:DiVA.org:liu-73582DiVA: diva2:474707
Funding agencies|DFG| SPP 1459 GRK 1570 |EU-ConceptGraphene||IB of BMBF at DLR||RFBR||Russian Ministry of Education and Sciences||Dynasty Foundation-ICFPM||2012-01-092012-01-092014-10-09