Spin current generation by edge plasmon M Shoufie Ukhtary(a*) , Yuan Tian (b), Riichiro Saito (b)
a) Research Center for Physics, Indonesian Institute of Sciences
* msho001[at]lipi.go.id
b) Department of Physics, Tohoku University
Abstract
Spin current is defined as the difference between charge currents of the spin up and down. The conventional method to generate spin current requires a magnetic material. In this work, we discuss the generation of spin current without magnetic material. Here, the spin current is generated by edge plasmon (EP) on a graphene ribbon. EP is an electromagnetic wave that propagates along the edges of the ribbon and the electric field is localized near the edges. In contrast with the surface plasmon on 3D metal, the electric field of EP rotates on the plane of graphene that corresponds to the transverse and out-of-plane optical spin. We found that the spin current flows on the surface of graphene with spin-polarization in the out-of-plane direction. Further, the spin current induced by EP is tunable not only by the frequency, but also by the Fermi energy of graphene, which enables application for a spin-switching device controlled by light and gate voltage
