Enhancement of anisotropic magnetoresistance in zigzag graphene nanodevices

We theoretically investigate the anisotropic charge transport behavior of zigzag graphene nanodots (zGNDs) connected to ferromagnetic nanoelectrodes. It turns out that when a zGND is attached to Ni-electrodes through S-linkers, the spin-polarized conductance exhibits oscillatory behavior with a maximum peak around θ ≈ 18°. A small change in the anisotropic spin polarization can thus cause a sudden jump in the device conductance. The two states of electronic conductance obtained by simply tuning the electrode magnetization may well serve as 1s and 0s to find potential utilities in designing spintronic logic circuits at the nanoscale.