We study the magnetotransport of high-mobility electrons in monolayer and bilayer ${\mathrm{MoSe}}_2$, which show Shubnikov–de Haas (SdH) oscillations and quantum Hall states in high magnetic fields. An electron effective mass of $0.8m_e$ is extracted from the SdH oscillations' temperature dependence; $m_e$ is the bare electron mass. At a fixed electron density the longitudinal resistance shows minima at filling factors (FFs) that are either predominantly odd, or predominantly even, with a parity that changes as the density is tuned. The SdH oscillations are insensitive to an in-plane magnetic field, consistent with an out-of-plane spin orientation of electrons at the $K$ point. We attribute the FF parity transitions to an interaction enhancement of the Zeeman energy as the density is reduced, resulting in an increased Zeeman-to-cyclotron energy ratio.

• Received 22 January 2018
• Revised 24 April 2018

DOI:https://doi.org/10.1103/PhysRevB.97.201407