Topological Insulators at Room Temperature.

Zhnag, H. ; Liu, C. ; Qi, X. ; Dai, X. ; Fang, Z. ; Zhang, S.

Technical Information Center Oak Ridge Tennessee

关键词: Electronic structure;    Energy gap;    Surface properties;    Antimony alloys;    Tellurium alloys;   

RP-ID  :  DE2010974186

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Topological insulators are new states of quantum matter with surface states protected by the time-reversal symmetry. In this work, we perform first-principle electronic structure calculations for Sb(sub 2)Te(sub 3), Sb(sub 2)Se(sub 3), Bi(sub 2)Te(sub 3) and Bi(sub 2)Se(sub 3) crystals. Our calculations predict that Sb(sub 2)Te(sub 3), Bi(sub 2)T e(sub 3) and Bi(sub 2)Se(sub 3) are topological insulators, while Sb(sub 2)Se(sub 3) is not. In particular, Bi(sub 2)Se(sub 3) has a topologically non-trivial energy gap of 0.3eV, suitable for room temperature applications. We present a simple and unified continuum model which captures the salient topological features of this class of materials. These topological insulators have robust surface states consisting of a single Dirac cone at the (Lambda) point.