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arXiv · 2401.04990

Catalyst-free MBE growth of PbSnTe nanowires with tunable aspect ratio

Mathijs G. C. Mientjes·Xin Guan·Pim J. H. Lueb·Marcel A. Verheijen·Erik P. A. M. Bakkers
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Abstract

Topological crystalline insulators (TCIs) are interesting for their topological surface states, which hold great promise for scattering-free transport channels and fault-tolerant quantum computing. A promising TCI is SnTe. However, Sn-vacancies form in SnTe, causing a high hole density, hindering topological transport from the surface being measured. This issue could be relieved by using nanowires with a high surface-to-volume ratio. Furthermore, SnTe can be alloyed with Pb reducing the Sn-vacancies while maintaining its topological phase. Here we present the catalyst-free growth of monocrystalline PbSnTe in molecular beam epitaxy (MBE). By the addition of a pre-deposition stage before the growth, we have control over the nucleation phase and thereby increase the nanowire yield. This facilitates tuning the nanowire aspect ratio by a factor of four by varying the growth parameters. These results allow us to grow specific morphologies for future transport experiments to probe the topological surface states in a Pb1-xSnxTe-based platform.

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Mathijs G. C. Mientjes, Xin Guan, Pim J. H. Lueb, Marcel A. Verheijen, Erik P. A. M. Bakkers. 2024-01-10. Catalyst-free MBE growth of PbSnTe nanowires with tunable aspect ratio. https://doi.org/10.1088/1361-6528%2Fad47c8

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