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arXiv · 1511.08939

Record Surface State Mobility and Quantum Hall Effect in Topological Insulator Thin Films via Interface Engineering

Nikesh Koirala·Matthew Brahlek·Maryam Salehi·Liang Wu·Jixia Dai·Justin Waugh·Thomas Nummy·Myung-Geun Han·Jisoo Moon·Yimei Zhu·Daniel Dessau·Weida Wu·N. Peter Armitage·Seongshik Oh
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Abstract

Material defects remain as the main bottleneck to the progress of topological insulators (TIs). In particular, efforts to achieve thin TI samples with dominant surface transport have always led to increased defects and degraded mobilities, thus making it difficult to probe the quantum regime of the topological surface states. Here, by utilizing a novel buffer layer scheme composed of an In2Se3/(Bi0.5In0.5)2Se3 heterostructure, we introduce a quantum generation of Bi2Se3 films with an order of magnitude enhanced mobilities than before. This scheme has led to the first observation of the quantum Hall effect in Bi2Se3.

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Nikesh Koirala, Matthew Brahlek, Maryam Salehi, Liang Wu, Jixia Dai, Justin Waugh, Thomas Nummy, Myung-Geun Han, Jisoo Moon, Yimei Zhu, Daniel Dessau, Weida Wu, N. Peter Armitage, Seongshik Oh. 2015-11-28. Record Surface State Mobility and Quantum Hall Effect in Topological Insulator Thin Films via Interface Engineering. https://doi.org/10.1021/acs.nanolett.5b03770

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