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arXiv · 2403.07864

Unraveling the nature of quasi van der Waals Epitaxy of magnetic topological insulators Cr: (BixSb1-x)2Te3 on a GaAs (111) substrate through coherently strained interface

Yuxing Ren·Lixuan Tai·Kaicheng Pan·Yueyun Chen·Benjamin Z. Gregory·Jin Ho Kang·Malcolm Jackson·Michael Liao·Yifei Sun·Noah Bodzin·Kin Wong·Suchismita Sarker·B. C. Regan·Chee-Wei Wong·Mark Goorsky·Andrej Singer·Kang L. Wang
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Abstract

Quasi van der Waals Epitaxy (qvdWE) has been realized for decades at the interfaces between 3D and 2D materials or van der Waals materials. The growth of magnetic topological insulators (MTI) Cr: (BixSb1-x)2Te3 (CBST) on GaAs (111) substrates for Quantum Anomalous Hall Effect (QAH) is actually one of the examples of qvdWE, which is not well noticed despite the fact that its advantages have been used in growth of various MTI materials. This is distinguished from the growth of MTIs on other substrates. Although the qvdWE mode has been used in many 2D growth on III-V substrates, the specific features and mechanisms are not well demonstrated and summarized yet. Here in this work, we have for the first time shown the features of both coherent interfaces and the existence of strain originating from qvdWE at the same time.

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Yuxing Ren, Lixuan Tai, Kaicheng Pan, Yueyun Chen, Benjamin Z. Gregory, Jin Ho Kang, Malcolm Jackson, Michael Liao, Yifei Sun, Noah Bodzin, Kin Wong, Suchismita Sarker, B. C. Regan, Chee-Wei Wong, Mark Goorsky, Andrej Singer, Kang L. Wang. 2024-03-12. Unraveling the nature of quasi van der Waals Epitaxy of magnetic topological insulators Cr: (BixSb1-x)2Te3 on a GaAs (111) substrate through coherently strained interface. https://arxiv.org/abs/2403.07864

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