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arXiv · 1702.05166

Density-Dependent Quantum Hall States and Zeeman Splitting in Monolayer and Bilayer WSe$_2$

Hema C. P. Movva·Babak Fallahazad·Kyounghwan Kim·Stefano Larentis·Takashi Taniguchi·Kenji Watanabe·Sanjay K. Banerjee·Emanuel Tutuc
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Abstract

We report a study of the quantum Hall states (QHSs) sequence of holes in mono- and bilayer WSe$_2$. The QHSs sequence transitions between predominantly even and predominantly odd filling factors as the hole density is tuned in the range $1.6 - 12\times10^{12}$ 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 WSe$_2$ 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.

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Hema C. P. Movva, Babak Fallahazad, Kyounghwan Kim, Stefano Larentis, Takashi Taniguchi, Kenji Watanabe, Sanjay K. Banerjee, Emanuel Tutuc. 2017-02-16. Density-Dependent Quantum Hall States and Zeeman Splitting in Monolayer and Bilayer WSe$_2$. https://doi.org/10.1103/physrevlett.118.247701

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