Controllable tuning of the spin-dependent transport in the graphene sheet

摘要

Based on the non-equilibrium Green's function in combination with the density-functional theory, the spin-dependent transport in the short graphene nanoribbon (graphene sheet) asymmetrically coupled to the electrodes of Au chains is investigated. It is found that a fully spin-polarized current (close to 100%) can be produced at the output port. The physics underlying attributes to the spatially separated edge states of the sheet caused by asymmetric contacts. Especially, the current's spin polarized direction can be tuned simply by changing the contact locations of the electrodes to the graphene sheet.