论文标题
直接观察一维PEIERLS型电荷密度浪潮在单层Mote的双边界$ _2 $
Direct Observation of One-Dimensional Peierls-Type Charge Density Wave in Twin Boundaries of Monolayer MoTe$_2$
论文作者
论文摘要
单层过渡金属二核苷（TMDC）中的一维（1D）金属镜 - 双边界（MTB）具有周期性的电荷调制，并为探索受限系统中的集体电子行为提供了理想的平台。电荷调制的基本机制以及电子如何在1D结构中传播。在这里，我们首次使用扫描隧道显微镜/光谱学（STM/ST）在单层MOTE2的MTB中，在一个周期内观察到电荷分布的原子尺度结构。共存明显的周期性晶格扭曲和U形能量隙清楚地表明了PEIERLS型电荷密度密度波（CDW）。沿着金属MTB的CDW间隙在CDW间隙之外进一步发现了等距的量化能级。密度功能理论（DFT）计算与间隙的电子结构非常吻合，并显示它们主要来自MO 4D轨道。我们的工作为金属MTBS上的1D PEIERLS型CDW提供了标志性证据，并提供了研究1D电荷调制的基础物理学的机会。
One-dimensional (1D) metallic mirror-twin boundaries (MTBs) in monolayer transition metal dichalcogenides (TMDCs) exhibit a periodic charge modulation and provide an ideal platform for exploring collective electron behavior in the confined system. The underlying mechanism of the charge modulation and how the electrons travel in 1D structures remain controversial. Here, for the first time, we observed atomic-scale structures of the charge distribution within one period in MTB of monolayer MoTe2 by using scanning tunneling microscopy/spectroscopy (STM/STS). The coexisting apparent periodic lattice distortions and U-shaped energy gap clearly demonstrate a Peierls-type charge density wave (CDW). Equidistant quantized energy levels with varied periodicity are further discovered outside the CDW gap along the metallic MTB. Density functional theory (DFT) calculations are in good agreement with the gapped electronic structures and reveal they originate mainly from Mo 4d orbital. Our work presents hallmark evidence of the 1D Peierls-type CDW on the metallic MTBs and offers opportunities to study the underlying physics of 1D charge modulation.
