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arXiv · 1207.1205

Unconventional Quantum Hall Effect and Tunable Spin Hall Effect in MoS2 Trilayers

Xiao Li·Fan Zhang·Qian Niu
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Abstract

We analyze the Landau level (LL) structure and spin Hall effect in a MoS2 trilayer. Due to orbital asymmetry, the low-energy Dirac fermions become heavily massive and the LL energies grow linearly with $B$, rather than with $\sqrt{B}$. Spin-orbital couplings break spin and valley degenerate LL's into two time reversal invariant groups, with LL crossing effects present in the valence bands. We find a field-dependent unconventional Hall plateau sequence $\nu=...$ $-2M-6$, $-2M-4$, $-2M-2$, $-2M-1$, ..., -5, -3, -1, 0, 2, 4 .... In a p-n junction, spin-resolved fractionally quantized conductance appears in two-terminal measurements with a controllable spin-polarized current that can be probed at the interface. We also show the tunability of zero-field spin Hall conductivity.

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Xiao Li, Fan Zhang, Qian Niu. 2012-07-05. Unconventional Quantum Hall Effect and Tunable Spin Hall Effect in MoS2 Trilayers. https://doi.org/10.1103/physrevlett.110.066803

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