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arXiv · 1709.04658

Restoration of Topological Surface State by Vacuum Annealing in Magnetically Doped Topological Insulator

Jinsu Kim·Eun-Ha Shin·Manoj K. Sharma·Kyuwook Ihm·Otgonbayar Dugerjav·Chanyong Hwang·Hwangho Lee·Kyung-Tae Ko·Jae-Hoon Park·Miyoung Kim·Hanchul Kim·Myung-Hwa Jung
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Abstract

The introduction of magnetic order on the surface of topological insulators in general breaks the two-dimensional character of topological surface state (TSS). Once the TSS disappears, it is improbable to restore the topological surface properties. In this report, we demonstrate that it is possible to restore the inherent TSS by ultra-high vacuum annealing. Starting from an antiferromagnetic Gd-doped Bi2Te3, that has surface state gap without TSS properties, after annealing we observed the gap closing as well as typical TSS features in physical properties. The microscopic mechanism of atomic migration and TSS restoration by annealing process is unraveled by the combination of scanning tunneling microscopy measurements and density functional theory calculations. This approach to control the surface of topological insulators and stabilize the TSS simply by vacuum annealing provides a new platform towards the exploitation of their topological properties.

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Jinsu Kim, Eun-Ha Shin, Manoj K. Sharma, Kyuwook Ihm, Otgonbayar Dugerjav, Chanyong Hwang, Hwangho Lee, Kyung-Tae Ko, Jae-Hoon Park, Miyoung Kim, Hanchul Kim, Myung-Hwa Jung. 2017-09-14. Restoration of Topological Surface State by Vacuum Annealing in Magnetically Doped Topological Insulator. https://arxiv.org/abs/1709.04658

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