论文标题
单层1T'-WTE2中的可调节的半学 - 学术绝缘体过渡
Strain Tunable Semimetal-Topological-Insulator Transition in Monolayer 1T'-WTe2
论文作者
论文摘要
量子自旋霍尔绝缘子（QSHI）由其传导边缘通道表现出来，该通道源自绝缘体积状态的非平凡拓扑。单层1T'-WTE2在传输测量中表现出了量化的边缘电导，但是由于其半金属性质，相干长度仅限于100 nm左右。为了克服这一限制，我们提出了一种应变工程技术来调整电子结构，在该技术中，沿着轴的压缩应变或沿B轴的A张拉伸应变可以将1T'-WTE2驱动到完整的间隙绝缘阶段。然后，对分子束外延和原位扫描隧道显微镜/光谱的联合研究证实了这种相变。同时，在菌株存在下发现拓扑边缘状态非常健壮。
A quantum spin hall insulator(QSHI) is manifested by its conducting edge channels that originate from the nontrivial topology of the insulating bulk states. Monolayer 1T'-WTe2 exhibits this quantized edge conductance in transport measurements, but because of its semimetallic nature, the coherence length is restricted to around 100 nm. To overcome this restriction, we propose a strain engineering technique to tune the electronic structure, where either a compressive strain along a axis or a tensile strain along b axis can drive 1T'-WTe2 into an full gap insulating phase. A combined study of molecular beam epitaxy and in-situ scanning tunneling microscopy/spectroscopy then confirmed such a phase transition. Meanwhile, the topological edge states were found to be very robust in the presence of strain.
