We report a study of the quantum Hall states (QHSs) sequence of holes in mono- and bilayer WSe2. The QHSs sequence transitions between predominantly even and predominantly odd filling factors as the hole density is tuned in the range 1.6−12×1012 cm−2. The QHSs sequence is insensitive to the transverse electric field, and tilted magnetic field measurements reveal an insensitivity of the QHSs sequence to the in-plane magnetic field, evincing that the hole spin is locked perpendicular to the WSe2 plane. These observations imply that the QHSs sequence is controlled by the Zeeman-to-cyclotron energy ratio, which remains constant as a function of perpendicular magnetic field at a fixed carrier density, but changes as a function of density due to strong electron-electron interaction.
@article{arxiv.1702.05166,
title = {Density-Dependent Quantum Hall States and Zeeman Splitting in Monolayer and Bilayer WSe$_2$},
author = {Hema C. P. Movva and Babak Fallahazad and Kyounghwan Kim and Stefano Larentis and Takashi Taniguchi and Kenji Watanabe and Sanjay K. Banerjee and Emanuel Tutuc},
journal= {arXiv preprint arXiv:1702.05166},
year = {2017}
}