Electronic structure-dependent magneto-optical Raman effect in atomically thin WS2. (4th June 2018)

• Record Type: Journal Article
• Authors: Du, Luojun; Jia, Zhiyan; Zhang, Qian; Zhang, Anmin; Zhang, Tingting; He, Rui; Yang, Rong; Shi, Dongxia; Yao, Yugui; Xiang, Jianyong; Zhang, Guangyu; Zhang, Qingming
• Is Part Of: 2D materials. Volume 5:Number 3(2018)
• Publication Date: 2018-06-04
• Subjects: magneto-optical Raman effect -- electronic structure -- WS2 -- optical mobility; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/aac593
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: Magneto-optical effect, such as Faraday rotation, magneto-optical Kerr and Zeeman effect, plays a fundamental role and has found extensive applications in condensed-matter physics. Two-dimensional transition metal dichalcogenides provide us an unprecedented platform for exploring abundant magneto-optical phenomena. Here we report such experiments that demonstrate the band structure-dependent magneto-optical Raman effect in atomically thin WS2 . Our experiments in conjunction with theoretical calculations uncover that the direct to indirect transition leads to distinct magneto-optical Raman effect between monolayer and bilayer/trilayer. We further quantitatively determine the optical mobility of carriers at different critical points of conduction band (K and Q points). In addition, our measurements reveal that not only the particular single-phonon mode A1g (Γ) but also multiple phonon replica and phonons at the edges of Brillouin zone display electronic structure-dependent gigantic magneto-optical Raman effect. Our work establishes a firm basis for benchmarking a new microscopic quantum Raman scattering theory, and paves a way towards novel magneto-optical applications based on 2D semiconductors.