Hofstadter spectra for d-orbital electrons: a case study on MoS₂
Yen-Hung Ho1,2*, Wu-Pei Su2, Ming-Fa Lin3
1Physics, National Tsing Hua University, Hsinchu, Taiwan
2Physics, University of Houston, Houston, Texas, United States of America
3Physics, National Cheng Kung University, Tainan, Taiwan
* presenting author:Yen-Hung Ho, email:yenhungho@gmail.com
In studying the Hofstadter problem of monolayer molybdenum disulfide (MoS₂), we systematically demonstrate the magnetic energy spectra due to various hoppings between d-orbital electrons. The magnetoelectronic spectrum shows a mirror symmetry as a result of the particle-hole symmetry in the Bloch bands. At small field, specific Landau fan diagrams can be ascribed to certain Bloch-band singularities. In the spectrum of real MoS₂, we further illustrate a breaking of spectral symmetry, the spin and valley polarization, and a flux-dependent energy gap. Our numerical results can facilitate the qualitative understanding of topological nature of d-bands and provide a basis for exploring the Landau levels in transition-metal dichalcogenides.

Keywords: Hofstadter spectrum, Transition metal dichalcogenides, Landau level