Valley-dependent Klein tunneling and spin-valley filter in silicene with magnetic barrier

Abstract

We have theoretically studied spin- and valley-transport properties in a silicene quantum structure with a square magnetic barrier modulated by off-resonant circularly polarized light (OCPL). The result shows that in the magnetic quantum structure, valley and spin filtering can be realized simultaneously with appropriate OCPL at small incident angles. More interestingly, at normal incidence, Klein tunneling is observed in the K′ valley. Besides, it is also found that valley polarization can be inverted by reversing the sign of the staggered potential or the chirality of OCPL. Nevertheless, the direction of spin polarization can only be modulated by the chirality of OCPL. These findings provide the potential applications for constructing novel type of silicene devices.