Band structures and topological properties of twisted bilayer MoTe2 and WSe2. (20th December 2021)

• Record Type: Journal Article
• Authors: Yu, Guiqiang; Wen, Lu; Luo, Guoyu; Wang, Yan
• Is Part Of: Physica scripta. Volume 96:Number 12(2021)
• Publication Date: 2021-12-20
• Subjects: transition metal dichalcogenides -- moiré superlattice -- effective continuum model -- Chern number -- band structure; Physics -- Periodicals; 530.05
• DOI: 10.1088/1402-4896/ac4192
• Languages: English
• ISSNs: 0031-8949

Abstract

Abstract: We calculate the electronic band structures and topological properties of twisted homobilayer transition metal dichalcogenides(t-TMDs), in particular, bilayer MoTe2 and WSe2 based on a low-energy effective continuum model. We systematically show how the twist angle, vertical electric field and pressure modify the band structures of t-TMDs, often accompanied by topological transitions.We find the variation of topological transitions mainly take place in a limited range of parameters. The electric field can efficiently tune the energy of the topmost second valence band to motify the Chern numbers of the topmost three valance bands. The topological property of the topmost first valance band can be modified by electric field and pressure, but doesn't depend on twist angle. We show the band gap between the topmost second and third valance bands that both change from non-trivial to trivial closes at κ − -point of the moiré Brillouin zone.