▎ 摘　　要

We study the pseudospin valve effect in bilayer graphene nanoribbons using the recursive Green's function method. The pseudospin degree of freedom is associated with the electron density in two layers and can be controlled by external gate electrodes. We find that the conductance of nanoribbons shows different behavior compared to infinite systems due to the appearance of edge states and quantum confinement. Remarkably, a large on-off ratio can be achieved in nanoribbons with zigzag edges, even when the Fermi energy lies in the bulk energy gap. The influence of possible edge vacancies and interface conditions is also discussed.