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arXiv · 1703.04042

Direct Visualization of 2D Topological Insulator in Single-layer 1T'-WTe2

Zhen-Yu Jia·Ye-Heng Song·Xiang-Bing Li·Kejing Ran·Pengchao Lu·Hui-Jun Zheng·Xin-Yang Zhu·Zhi-Qiang Shi·Jian Sun·Jinsheng Wen·Dingyu Xing·Shao-Chun Li
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Abstract

We grow nearly freestanding single-layer 1T'-WTe2 on graphitized 6H-SiC(0001) by using molecular beam epitaxy (MBE), and characterize its electronic structure with scanning tunneling microscopy / spectroscopy (STM/STS). We demonstrate the existence of topological edge states at the periphery of single-layer WTe2 islands. Surprisingly, we also find a band gap in the bulk and the semiconducting behaviors of the single-layer WTe2 at low temperature, which is likely resulted from an incommensurate charge density wave (CDW) transition. The realization of two-dimensional topological insulators (2D TIs) in single-layer transition metal dichalcogenide (TMD) thus provides a promising platform for further exploration of the 2D TIs' physics and related applications.

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Zhen-Yu Jia, Ye-Heng Song, Xiang-Bing Li, Kejing Ran, Pengchao Lu, Hui-Jun Zheng, Xin-Yang Zhu, Zhi-Qiang Shi, Jian Sun, Jinsheng Wen, Dingyu Xing, Shao-Chun Li. 2017-03-11. Direct Visualization of 2D Topological Insulator in Single-layer 1T'-WTe2. https://doi.org/10.1103/physrevb.96.041108

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