Heavy carrier effective masses in van der Waals semiconductor Sn(SeS) revealed by high magnetic fields up to 150 T

Yang, Zhuo; Wang, Xueting; Felton, James; Kudrynskyi, Zakhar; Gen, Masaki; Nomura, Toshihiro; Wang, Xinjiang; Eaves, Laurence; Kovalyuk, Zakhar D; Kohama, Yoshimitsu; Zhang, Lijun; Patanè, Amalia

Abstract

The SnSe2(1-x)S2x alloy is a van der Waals semiconductor with versatile, tunable electronic properties and prospects for future applications ranging from electronics to thermoelectrics and superconductivity. Its band structure and carrier effective masses underlie the quantum behavior of charge carriers and hold great promise in future technologies. However, experimental measurement of these properties remains a challenging task. Here magnetotransmission spectroscopy of SnSe2(1-x)S2x thin films at pulsed magnetic fields B of up to 150 T reveals a large electron-hole reduced cyclotron mass μ∗> 0.454 me (me is the free electron mass). This finding is supported by first-principle calculations of the band structure and by semiclassical Boltzmann transport theory, which predict a pronounced anisotropy of the carrier effective masses and electrical conductivity over two orthogonal directions (namely in the layer plane and out-of-plane) with a different anisotropy for electrons and holes. These properties are unique and important features of this class of compounds and are critical for understanding and using the tunable band structure of SnSe2(1-x)S2x in fundamental and applied research.

• Journal Article Type: Article
• Acceptance Date: Aug 4, 2021
• Online Publication Date: Aug 24, 2021
• Publication Date: Aug 15, 2021
• Deposit Date: Aug 6, 2021
• Publicly Available Date: Aug 15, 2021
• Journal: Physical Review B
• Print ISSN: 0163-1829
• Electronic ISSN: 2469-9969
• Peer Reviewed: Peer Reviewed
• Volume: 104
• Issue: 8
• Article Number: 085206
• DOI: https://doi.org/10.1103/PhysRevB.104.085206
• Public URL: https://nottingham-repository.worktribe.com/output/5957251
• Publisher URL: https://journals.aps.org/prb/abstract/10.1103/PhysRevB.104.085206