Velocity barrier-controlled of spin-valley polarized transport in monolayer WSe2 junction. (May 2018)

• Record Type: Journal Article
• Authors: Qiu, Xuejun; Lv, Qiang; Cao, Zhenzhou
• Is Part Of: Superlattices and microstructures. Volume 117(2018)
• Page Start: 449
• Page End: 456
• Publication Date: 2018-05
• Subjects: Spin -- Valley -- Polarization -- WSe2 -- Velocity barrier; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2018.03.082
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: In this work, we have theoretically investigated the influence of velocity barrier on the spin-valley polarized transport in monolayer (ML) WSe2 junction with a large spin-orbit coupling (SOC). Both the spin-valley resolved transmission probabilities and conductance are strong dependent on the velocity barrier, as the velocity barrier decreases to 0.06, a spin-valley polarization of exceeding 90% is observed, which is distinct from the ML MoS2 owing to incommensurable SOC. In addition, the spin-valley polarization is further increased above 95% in a ML WSe2 superlattice, in particular, it's found many extraordinary velocity barrier-dependent transport gaps for multiple barrier due to evanescent tunneling. Our results may open an avenue for the velocity barrier-controlled high-efficiency spin and valley polarizations in ML WSe2 -based electronic devices. Highlights: The spin-valley resolved transmission probabilities and conductance are strong dependent on the velocity barrier. A spin-valley polarization of exceeding 90% is observed as the velocity barrier decreases to 0.06. Many extraordinary velocity barrier-dependent transport gaps are found in ML WSe2 superlattice due to evanescent tunneling. The spin-valley polarization is further increased above 95% in a ML WSe2 superlattice.