Spin electronic manipulation based on zigzag-edgegraphene nanojunction with a line defect

We investigate the transport of spin electron through the zigzag-edge graphene nanojunction with a line defect. When the magnetization is zero, the conductance spectra exhibits a well-defined insulating band around the point far away from Dirac point. And the width of the insulating band is exactly equal to the energy splitting between the lowest conduction band of the left lead and the new state of the device region. For the parallel configuration, with the enhancement of the magnetization, the conductance value will be reduced by half around the Dirac point. For the antiparallel configuration, the width of the well-defined insulating band becomes larger with the rising of the magnetization. (paper)