One-dimensional topological edge states of bismuth bilayers
One-dimensional topological edge states of bismuth bilayers
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DOI：
10.1038/nphys3048
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发表时间：
2014-09-01
期刊：
影响因子：
19.6
通讯作者：
Yazdani, Ali
中科院分区：
文献类型：
--
作者：
Drozdov, Ilya K.;Alexandradinata, A.;Yazdani, Ali
受时间反演对称性保护的二维物质拓扑绝缘态的标志是存在手性边缘模式，该模式沿着样品的周边传播。在第一个被预测为二维拓扑绝缘体的系统中，有铋的双层。在这里，我们报告的扫描隧道显微镜实验散装Bi晶体，表明预测的Bi-双层的边缘状态的一个子集从基板的状态去耦，并提供直接的光谱证据，其一维性质。此外，通过可视化的量子干涉的边缘模式准粒子在受限的几何形状，我们证明了他们显着的相干传播沿着的边缘与散射特性一致的强抑制反向散射的预测传播的拓扑边缘状态。
The hallmark of a topologically insulating state of matter in two dimensions protected by time-reversal symmetry is the existence of chiral edge modes propagating along the perimeter of the sample. Among the first systems predicted to be a two-dimensional topological insulator are bilayers of bismuth. Here we report scanning tunnelling microscopy experiments on bulk Bi crystals that show that a subset of the predicted Bi-bilayers' edge states are decoupled from the states of the substrate and provide direct spectroscopic evidence of their one-dimensional nature. Moreover, by visualizing the quantum interference of edge-mode quasi-particles in confined geometries, we demonstrate their remarkable coherent propagation along the edge with scattering properties consistent with strong suppression of backscattering as predicted for the propagating topological edge states.