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arXiv · 1204.3816

Beta-Ag2Te: A topological insulator with strong anisotropy

Azat Sulaev·Peng Ren·Bin Xia·Qing Hua Lin·Ting Yu·Caiyu Qiu·Shuang-Yuan Zhang·Ming-Yong Han·Zhi Peng Li·Wei Guang Zhu·Qingyu Wu·Yuan Ping Feng·Lei Shen·Shun-Qing Shen·Lan Wang
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Abstract

We present evidence of topological surface states in beta-Ag2Te through first-principles calculations and periodic quantum interference effect in single crystalline nanoribbon. Our first-principles calculations show that beta-Ag2Te is a topological insulator with a gapless Dirac cone with strong anisotropy. To experimentally probe the topological surface state, we synthesized high quality beta-Ag2Te nanoribbons and performed electron transport measurements. The coexistence of pronounced Aharonov-Bohm oscillations and weak Altshuler-Aronov-Spivak oscillations clearly demonstrates coherent electron transport around the perimeter of beta-Ag2Te nanoribbon and therefore the existence of metallic surface states, which is further supported by the temperature dependence of resistivity for beta-Ag2Te nanoribbons with different cross section areas. Highly anisotropic topological surface state of beta-Ag2Te suggests that the material is a promising material for fundamental study and future spintronic devices.

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Azat Sulaev, Peng Ren, Bin Xia, Qing Hua Lin, Ting Yu, Caiyu Qiu, Shuang-Yuan Zhang, Ming-Yong Han, Zhi Peng Li, Wei Guang Zhu, Qingyu Wu, Yuan Ping Feng, Lei Shen, Shun-Qing Shen, Lan Wang. 2012-04-17. Beta-Ag2Te: A topological insulator with strong anisotropy. https://arxiv.org/abs/1204.3816

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