Spin and valley filter based on two-dimensional WSe2 heterostructures
Abstract
In this work, we investigate spin and valley transport properties of a WSe2 monolayer placed on top of a ferromagnetic insulator. We are interested in controlling the transport properties by applying external potentials to the system. To obtain spin an valley polarizations, we have considered a single and a double barrier structure with gate potentials. We have analyzed how the efficiency of these polarized transport properties depend on the gate-potential intensities and geometrical configurations. Additionally, we investigate how the spin and valley transport properties are modified when an ac-potential is applied to the system. We have obtained a controllable modulation of the spin and valley polarizations as a function of the intensity and frequency of the ac-potential, mainly in the terahertz range. These results validate the proposal of double quantum well structures of WSe2 as candidates to provide spin and valley dependent transport within an optimal geometrical parameter regime.