AVS 59th Annual International Symposium and Exhibition
    Graphene and Related Materials Focus Topic Thursday Sessions
       Session GR+AS+NS+SS-ThM

Invited Paper GR+AS+NS+SS-ThM5
Growth of a Linear Topological Defect in Graphene as a Gate-tunable Valley Valve

Thursday, November 1, 2012, 9:20 am, Room 13

Session: Graphene Nanostructures
Presenter: A. Zettl, Univ. of California at Berkeley, Lawrence Berkeley Lab
Authors: A. Zettl, Univ. of California at Berkeley, Lawrence Berkeley Lab
J.-H. Chen, Univ. of California at Berkeley, Lawrence Berkeley Lab
N. Alem, Univ. of California at Berkeley, Lawrence Berkeley Lab
G. Autes, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland
F. Gargiulo, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland
A. Gautam, Lawrence Berkeley National Lab
M. Linck, Lawrence Berkeley National Lab
C. Kisielowski, Lawrence Livermore National Lab
O.V. Yazyev, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland
S.G. Louie, Univ. of California at Berkeley, Lawrence Berkeley Lab
Correspondent: Click to Email
The valleytronics, a zero-magnetic-field equivalent of spintronics, could be realized in graphene if a simple scheme can be conceived to generate and to detect valley polarization in the material. Here we provide the first direct experimental observation of the self-sustained, atomically controlled growth of a peculiar linear defect structure in suspended graphene. The structure consists in units of octagon and pentagon pairs (termed 5-5-8 defect) and can be grown from a single pentagon seed in graphene under electrical bias. First-principle simulations show that the 5-5-8 defect can act as a gate-tunable valley valve. The result represents a critical step towards realizing valleytronics in graphene.