Department of Chemistry, National University of Singapore, 3 Science Driver 3, Singapore 117543, Singapore.
Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore 117546, Singapore.
Nat Commun. 2016 Oct 4;7:12904. doi: 10.1038/ncomms12904.
Reducing the dimensionality of transition metal dichalcogenides to one dimension opens it to structural and electronic modulation related to charge density wave and quantum correlation effects arising from edge states. The greater flexibility of a molecular scale nanowire allows a strain-imposing substrate to exert structural and electronic modulation on it, leading to an interplay between the curvature-induced influences and intrinsic ground-state topology. Herein, the templated growth of MoS nanowire arrays consisting of the smallest stoichiometric MoS building blocks is investigated using scanning tunnelling microscopy and non-contact atomic force microscopy. Our results show that lattice strain imposed on a nanowire causes the energy of the edge states to oscillate periodically along its length in phase with the period of the substrate topographical modulation. This periodic oscillation vanishes when individual MoS nanowires join to form a wider nanoribbon, revealing that the strain-induced modulation depends on in-plane rigidity, which increases with system size.
将过渡金属二卤化物的维度降低到一维，使其能够进行结构和电子调制，这些调制与电荷密度波和量子相关效应有关，这些效应源于边缘态。分子尺度纳米线的更大灵活性允许应变施加衬底对其进行结构和电子调制，从而导致曲率诱导的影响与固有基态拓扑结构之间的相互作用。本文通过扫描隧道显微镜和非接触原子力显微镜研究了由最小化学计量比 MoS 构建块组成的 MoS 纳米线阵列的模板生长。我们的结果表明，施加在纳米线上的晶格应变会导致边缘态的能量沿着纳米线的长度周期性地振荡，与衬底形貌调制的周期同步。当单个 MoS 纳米线连接形成更宽的纳米带时，这种周期性振荡消失，这表明应变诱导的调制取决于面内刚度，随着系统尺寸的增加而增加。
