Details

Autor(en) / Beteiligte

• Chuang, Feng-Chuan
• Hsu, Chia-Hsiu
• Chou, Hsin-Lei
• Crisostomo, Christian P.
• Huang, Zhi-Quan
• Wu, Shih-Yu
• Kuo, Chien-Cheng
• Yeh, Wang-Chi V.
• Lin, Hsin
• Bansil, Arun

Titel

Prediction of two-dimensional topological insulator by forming a surface alloy on Au/Si(111) substrate

Ist Teil von

• Physical review. B, 2016-01, Vol.93 (3), Article 035429

Ort / Verlag

United States: American Physical Society

Erscheinungsjahr

2016

Link zum Volltext

Quelle

American Physical Society Journals

Beschreibungen/Notizen

• Two-dimensional (2D) topological insulators (TIs), which can be integrated into the modern silicon industry, are highly desirable for spintronics applications. Here, using first-principles electronic structure calculations, we show that the Au/Si(111)-3 substrate can provide a platform for hosting 2D TIs obtained through the formation of surface alloys with a honeycomb pattern of adsorbed atoms. We systematically examined elements from groups III to VI of the periodic table at 2/3 monolayer coverage on Au/Si(111)-3, and found that In, Tl, Ge, and Sn adsorbates result in topologically nontrivial phases with band gaps varying from 0 to 50 meV. Our scanning tunneling microscopy and low-energy electron diffraction experiments confirm the presence of the honeycomb pattern when Bi atoms are deposited on Au/Si(111)-3, in accord with our theoretical predictions. Our findings pave the way for using surface alloys as a potential route for obtaining viable 2D TI platforms.