• 文献标题:   Valley and Zeeman Splittings in Multilayer Epitaxial Graphene Revealed by Circular Polarization Resolved Magneto-infrared Spectroscopy
  • 文献类型:   Article
  • 作  者:   JIANG YX, LU ZG, GIGLIOTTI J, RUSTAGI A, CHEN L, BERGER C, DE HEER W, STANTON CJ, SMIMOV D, JIANG ZG
  • 作者关键词:   epitaxial graphene, symmetry breaking state, landau level, magnetoinfrared spectroscopy
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   Georgia Inst Technol
  • 被引频次:   3
  • DOI:   10.1021/acs.nanolett.9b02505
  • 出版年:   2019

▎ 摘  要

Circular-polarization-resolved magneto-infra-red studies of multilayer epitaxial graphene (MEG) are performed using tunable quantum cascade lasers in high magnetic fields up to 17.5 T. Landau level (LL) transitions in the monolayer and bilayer graphene inclusions of MEG are resolved, and considerable electron-hole asymmetry is observed in the extracted electronic band structure. For monolayer graphene, a four-fold splitting of the n = 0 to n = 1 LL transition is evidenced and attributed to the lifting of the valley and spin degeneracy of the zeroth LL and the broken electron-hole symmetry. The magnetic field dependence of the splitting further reveals its possible mechanisms. The best fit to experimental data yields effective g-factors, g(VS)* = 6.7 and g(ZS)* = 4.8, for the valley and Zeeman splittings, respectively.