▎ 摘　　要

Using the non-equilibrium Green's function method and within the framework of the tight-binding Hamiltonian model in Landauer-Buttiker formalism, the spin-dependent transport and tunnel magnetoresistance (TMR) of AAA- and ABC-stacked trilayer zigzag graphene nanoribbon (TLG) connected to two ferromagnetic (FM) semiinfinite single-layer zigzag graphene nanoribbons (FM/TLG/FM system) have been theoretically investigated. Results show that the TMR for both AAA- and ABC-stacked cases can be increased about 100% because of the band-selective rule, and the magnitude of this 100% TMR region, enhances with the increase of the magnetization strength in FM graphene nanoribbon electrodes. Also, the TLG dimension has a prominent effect on the TMR ratio of the system. It is shown that the large values of the TMR ratio can be achieved very nicely by the variation of the width and length of the FM/TLG/FM system. The present theoretical results may be useful for designing few-layer graphene-based spin valves.