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

TL;DR

This paper reports the discovery of natural van der Waals heterostructures combining magnetic and topological properties, providing a promising platform for quantum topological phenomena research.

Contribution

It introduces natural magnetic heterostructures of (MnBi2Te4)m(Bi2Te3)n with controllable magnetism and preserved topological surface states, advancing material synthesis for quantum applications.

Findings

Weaker interlayer antiferromagnetic coupling with increased layer separation.

Observation of anomalous Hall effect coupled with magnetization below 5 K.

Homogeneous heterostructures with atomically sharp interfaces and intrinsic magnetic properties.

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.