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arXiv · 1905.02385

Natural van der Waals heterostructural single crystals with both magnetic and topological properties

Jiazhen Wu·Fucai Liu·Masato Sasase·Koichiro Ienaga·Yukiko Obata·Ryu Yukawa·Koji Horiba·Hiroshi Kumigashira·Satoshi Okuma·Takeshi Inoshita·Hideo Hosono
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Abstract

Heterostructures having both magnetism and topology are promising materials for the realization of exotic topological quantum states while challenging in synthesis and engineering. Here, we report natural magnetic van der Waals heterostructures of (MnBi2Te4)m(Bi2Te3)n that exhibit controllable magnetic properties while maintaining their topological surface states. The interlayer antiferromagnetic exchange coupling is gradually weakened as the separation of magnetic layers increases, and an anomalous Hall effect that is well coupled with magnetization and shows ferromagnetic hysteresis was observed below 5 K. The obtained homogeneous heterostructure with atomically sharp interface and intrinsic magnetic properties will be an ideal platform for studying the quantum anomalous Hall effect, axion insulator states, and the topological magnetoelectric effect.

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Jiazhen Wu, Fucai Liu, Masato Sasase, Koichiro Ienaga, Yukiko Obata, Ryu Yukawa, Koji Horiba, Hiroshi Kumigashira, Satoshi Okuma, Takeshi Inoshita, Hideo Hosono. 2019-05-07. Natural van der Waals heterostructural single crystals with both magnetic and topological properties. https://doi.org/10.1126/sciadv.aax9989

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