▎ 摘　　要

We have theoretically investigated the spin transport properties and tunnel magnetoresistance of the double junction, which consists of the fifth-stage Thue-Morse graphene superiattice (TMGSL) or periodic graphene superlattice (PGSL) and three ferromagnetic graphene (FG) electrodes. The results indicate that the middle ferromagnetic graphene stripe can lead to obvious defect effect on the conductance. Meanwhile, the FG/TMGSL double junction possesses more marked defect effect when compared to the FG/PGSL double junction, along with larger and more irregular oscillation conductance and tunnel magnetoresistance. (C) 2014 Elsevier B.V. All rights reserved.