title: Electrically controllable sudden reversals in spin and valley polarization in silicene.
abstract: We study the spin and valley dependent transport in a silicene superlattice under the influence of a magnetic exchange field, a perpendicular electric field and a voltage potential. It is found that a gate-voltage-controllable fully spin and valley polarized current can be obtained in the proposed device, and the spin and valley polarizations are sensitive oscillatory functions of the voltage potential. In properly designed superlattice structure, the spin and valley polarizations can be reversed from -100% to 100% by a slight change in the external voltage potential. The energy dispersion relations of the superlattice structure are also investigated, which helps us to understand the effects of the superlattice structure. The switching of the spin direction and the valley of the tunneling electrons by a gate voltage enables new possibilities for spin or valley control in silicene-based spintronics and valleytronics.
authors.affiliation: School of Materials and Energy, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China.
authors.forename: Qingtian
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, People's Republic of China.|City University of Hong Kong Shenzhen Research Institute, Shenzhen, 5183000, People's Republic of China.
authors.forename: K S
authors.initials: KS
authors.lastname: Chan
authors.affiliation: School of Materials and Energy, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China.
authors.forename: Jingbo
authors.initials: J
authors.lastname: Li