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arXiv · 1012.5716

Growth of quantum well films of topological insulator Bi2Se3 on insulating substrate

Cui-Zu Chang·Ke He·Min-Hao Liu·Zuo-Cheng Zhang·Xi Chen·Li-Li Wang·Xu-Cun Ma·Ya-Yu Wang·Qi-Kun Xue
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Abstract

Insulating substrates are crucial for electrical transport study and room temperature application of topological insulator films at thickness of only several nanometers. High quality quantum well films of Bi2Se3, a typical three-dimensional topological insulator, have been grown on α-Al2O3 (sapphire) (0001) by molecular beam epitaxy. The films exhibit well-defined quantum well states and surface states, suggesting the uniform thickness over macroscopic area. The Bi2Se3 thin films on sapphire (0001) provide a good system to study low-dimensional physics of topological insulators since conduction contribution from the substrate is negligibly small.

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Cui-Zu Chang, Ke He, Min-Hao Liu, Zuo-Cheng Zhang, Xi Chen, Li-Li Wang, Xu-Cun Ma, Ya-Yu Wang, Qi-Kun Xue. 2010-12-28. Growth of quantum well films of topological insulator Bi2Se3 on insulating substrate. https://doi.org/10.1142/s2010324711000033

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