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arXiv · 2107.08365

Bilayer Quantum Hall States in an n-type Wide Tellurium Quantum Well

Chang Niu·Gang Qiu·Yixiu Wang·Mengwei Si·Wenzhuo Wu·Peide D. Ye
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Abstract

Tellurium (Te) is a narrow bandgap semiconductor with a unique chiral crystal structure. The topological nature of electrons in the Te conduction band can be studied by realizing n-type doping using atomic layer deposition (ALD) technique on two-dimensional (2D) Te film. In this work, we fabricated and measured the double-gated n-type Te Hall-bar devices, which can operate as two separate or coupled electron layers controlled by the top gate and back gate. Profound Shubnikov-de Haas (SdH) oscillations are observed in both top and bottom electron layers. Landau level hybridization between two layers, compound and charge-transferable bilayer quantum Hall states at filling factor 4, 6, and 8 are analyzed. Our work opens the door for the study of Weyl physics in coupled bilayer systems of 2D materials.

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Chang Niu, Gang Qiu, Yixiu Wang, Mengwei Si, Wenzhuo Wu, Peide D. Ye. 2021-07-18. Bilayer Quantum Hall States in an n-type Wide Tellurium Quantum Well. https://doi.org/10.1021/acs.nanolett.1c01705

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