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arXiv · 2506.02466

Reconstructing the wavefunction of magnetic topological insulators MnBi2Te4 and MnBi4Te7 using spin-resolved photoemission

Xue Han·Jason Qu·Hengxin Tan·Zicheng Tao·Noah M. Meyer·Patrick S. Kirchmann·Yanfeng Guo·Binghai Yan·Zhi-Xun Shen·Jonathan A. Sobota
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Abstract

Despite their importance for exotic quantum effects, the surface electronic structure of magnetic topological insulators MnBi2Te4 and MnBi4Te7 remains poorly understood. Using high-efficiency spin- and angle-resolved photoemission spectroscopy, we directly image the spin-polarization and orbital character of the surface states in both compounds and map our observations onto a model wavefunction to describe the complex spin-orbital texture, which solidifies our understanding of the surface band structure by establishing the single-band nature of the most prominent states. Most importantly, our analysis reveals a new mechanism for reducing the magnetic gap of the topological surface states based on the orbital composition of the wavefunction.

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Xue Han, Jason Qu, Hengxin Tan, Zicheng Tao, Noah M. Meyer, Patrick S. Kirchmann, Yanfeng Guo, Binghai Yan, Zhi-Xun Shen, Jonathan A. Sobota. 2025-06-03. Reconstructing the wavefunction of magnetic topological insulators MnBi2Te4 and MnBi4Te7 using spin-resolved photoemission. https://doi.org/10.1103/lfxc-lsc1

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