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Based on the tight binding model and Keldysh non-equilibrium Green’s function method, we investigated the single parameter non-adiabatic quantum spin pumping phenomenon in zigzag silicene nanoribbon. Quantum pumping consists of two opposite photon-assisted processes, namely the photon-absorption process and the photon-excitation process, which can drive charge carriers flowing in opposite directions. The perpendicular electric field can significantly alter the leftwards/rightwards propagation velocity as well as the tunneling probability in the low-energy region but has opposite influence on the two spin species. Therefore, applying a vertical electric field can destroy the symmetry of the photon-assisted processes, where the leftwards/rightwards transmission of one spin species is enhanced/weakened while the situation is exactly the opposite for the other spin, resulting in spin polarized currents. The pure spin current can occur at zero Fermi energy and the spin polarization can be inverted from 1 to -1 by tuning the driving frequencies. This study is expected to achieve the electrical controllable quantum spin pumping based on silicene nanoribbon, independent of any ferromagnetic elements.








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