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arXiv · 1908.11495

Quantum Hall Effect of Weyl Fermions in Semiconducting n-type Tellurene

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

Dirac and Weyl nodal materials can host low-energy relativistic quasiparticles. Under strong magnetic fields, the topological properties of Dirac/Weyl materials can directly manifest through quantum Hall states. However, most Dirac/Weyl nodes generically exist in semimetals without exploitable bandgaps due to their accidental band-crossing origin. Here we report the first experimental observation of Weyl fermions in a semiconductor. Tellurene, the 2D form of tellurium, possesses chiral crystal structure which induces unconventional Weyl nodes with a hedgehog-like radial spin texture near the conduction band edge. We synthesize high-quality n-type tellurene by a hydrothermal method with subsequent dielectric doping and detect a topologically non-trivial pi Berry phase in quantum Hall sequences. Our work expands the spectrum of Weyl matter into semiconductors and offers a new platform to design novel quantum devices by marrying the advantages of topological materials to versatile semiconductors.

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Gang Qiu, Chang Niu, Yixiu Wang, Mengwei Si, Zhuocheng Zhang, Wenzhuo Wu, Peide D. Ye. 2019-08-30. Quantum Hall Effect of Weyl Fermions in Semiconducting n-type Tellurene. https://doi.org/10.1038/s41565-020-0715-4

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