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arXiv · 1801.03474

Tunable $\Gamma - K$ Valley Populations in Hole-Doped Trilayer WSe$_2$

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

We present a combined experimental and theoretical study of valley populations in the valence bands of trilayer WSe$_2$. Shubnikov$-$de Haas oscillations show that trilayer holes populate two distinct subbands associated with the $K$ and $\Gamma$ valleys, with effective masses 0.5$m_e$ and $1.2m_e$, respectively; $m_e$ is the bare electron mass. At a fixed total hole density, an applied transverse electric field transfers holes from $\Gamma$ orbitals to $K$ orbitals. We are able to explain this behavior in terms of the larger layer polarizability of the $K$ orbital subband.

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Hema C. P. Movva, Timothy Lovorn, Babak Fallahazad, Stefano Larentis, Kyounghwan Kim, Takashi Taniguchi, Kenji Watanabe, Sanjay K. Banerjee, Allan H. MacDonald, Emanuel Tutuc. 2018-01-10. Tunable $\Gamma - K$ Valley Populations in Hole-Doped Trilayer WSe$_2$. https://doi.org/10.1103/physrevlett.120.107703

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