Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Proc Natl Acad Sci U S A. 2011 Jan 4;108(1):24-8. doi: 10.1073/pnas.1019040108. Epub 2010 Dec 20.
We report a successful observation of pressure-induced superconductivity in a topological compound Bi(2)Te(3) with T(c) of ∼3 K between 3 to 6 GPa. The combined high-pressure structure investigations with synchrotron radiation indicated that the superconductivity occurred at the ambient phase without crystal structure phase transition. The Hall effects measurements indicated the hole-type carrier in the pressure-induced superconducting Bi(2)Te(3) single crystal. Consequently, the first-principles calculations based on the structural data obtained by the Rietveld refinement of X-ray diffraction patterns at high pressure showed that the electronic structure under pressure remained topologically nontrivial. The results suggested that topological superconductivity can be realized in Bi(2)Te(3) due to the proximity effect between superconducting bulk states and Dirac-type surface states. We also discuss the possibility that the bulk state could be a topological superconductor.
我们报告了在拓扑化合物 Bi(2)Te(3)中观察到压力诱导超导的成功，在 3 到 6 GPa 之间 T(c)约为 3 K。结合同步辐射的高压结构研究表明，超导发生在环境相中，没有晶体结构相变。霍尔效应测量表明，在压力诱导超导 Bi(2)Te(3)单晶中存在空穴型载流子。因此，基于高压下 X 射线衍射图谱的 Rietveld 精修得到的结构数据的第一性原理计算表明，电子结构在压力下仍然具有拓扑非平庸性。结果表明，由于超导体态和 Dirac 型表面态之间的近邻效应，Bi(2)Te(3)中可以实现拓扑超导。我们还讨论了体态可能是拓扑超导体的可能性。
