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arXiv · 1101.0667

Topological Aspect and Quantum Magnetoresistance of $β$-Ag$_2$Te

Wei Zhang·Rui Yu·Wanxiang Feng·Yugui Yao·Hongming Weng·Xi Dai·Zhong Fang
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Abstract

To explain the unusual non-saturating linear magnetoresistance observed in silver chalcogenides, the quantum scenario has been proposed based on the assumption of gapless linear energy spectrum. Here we show, by first principles calculations, that $β$-Ag$_2$Te with distorted anti-fluorite structure is in fact a topological insulator with gapless Dirac-type surface states. The characteristic feature of this new binary topological insulator is the highly anisotropic Dirac cone, in contrast to known examples, such as Bi$_2$Te$_3$ and Bi$_2$Se$_3$. The Fermi velocity varies an order of magnitude by rotating the crystal axis.

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Wei Zhang, Rui Yu, Wanxiang Feng, Yugui Yao, Hongming Weng, Xi Dai, Zhong Fang. 2011-08-08. Topological Aspect and Quantum Magnetoresistance of $β$-Ag$_2$Te. https://doi.org/10.1103/physrevlett.106.156808

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