▎ 摘　　要

Electron transport through a quantum wire coupled with ferromagnetic leads on a graphene sheet is studied by the Keldysh nonequilibrium Green's function method. We investigate the dependence of the transport properties on the wire-graphene coupling strength in detail. It is found that the peaks of the density of states fade away and the current is suppressed with the increasing wire-graphene coupling strength. The spin polarized strength of the two leads can effectively suppress the current and the transmission. The results obtained provide valuable theoretical guidance to the spintronics experiment. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4773913]