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Updated: Sep 9, 2025
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Strongly enhanced topological quantum phases in dual-surface AlOx-encapsulated MnBi2Te4
Zichen Lian1, Yongqian Wang2, Yongchao Wang1
1State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China.
Abstract:
The topological quantum phases in antiferromagnetic topological insulator MnBi2Te4 hold promise for next-generation spintronics, but their experimental realization has been constrained by challenges in preparing high-quality devices. In this work, we report a new wax-assisted exfoliation and transfer method that enables the fabrication of MnBi2Te4 heterostructures with both surfaces encapsulated by AlOx. This strategy strongly enhances the transport performances of the topological quantum phases in MnBi2Te4 flakes, which is attributed to the enhancement of magnetism by the AlOx layer. We observe the robust axion insulator state in even-layer device with wide zero Hall plateau and high longitudinal resistivity, and the quantum anomalous Hall effect in odd-layer device with large hysteresis and sharp plateau transition. These results demonstrate that the combination of wax exfoliation and AlOx encapsulation provides great potentials for exploring novel topological quantum phenomena and potential applications in MnBi2Te4 and other two-dimensional materials.
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