We explore the impact of edge states in three types of transition metal dichalcogenides (TMDs), namely metallic Td-phase WTe₂ and semiconducting 2H-phase MoTe₂ and MoS₂, by patterning thin flakes into ribbons with varying channel widths. No obvious charge depletion at the edges is observed for any of these three materials, in contrast to observations made for graphene nanoribbon devices. The semiconducting ribbons are characterized in a three-terminal field-effect transistor (FET) geometry. In addition, two ribbon array designs have been carefully investigated and found to exhibit current levels higher than those observed for conventional one-channel devices. Our results suggest that device structures incorporating a high number of edges can improve the performance of TMD FETs. This improvement is attributed to a higher local electric field, resulting from the edges, increasing the effective number of charge carriers, and the absence of any detrimental edge-related scattering.

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我们探讨了边缘态对三种类型的过渡金属二硫化二氢（TMDs）的影响，即金属Td相WTe ₂和半导体2H相MoTe ₂和MoS ₂，通过将细薄片图案化成具有变化的通道宽度的色带。与对石墨烯纳米带器件所做的观察相反，对于这三种材料中的任何一种，在边缘均未观察到明显的电荷耗尽。半导体带具有三端场效应晶体管（FET）的几何形状。此外，已经仔细研究了两种带状阵列设计，发现它们的电流水平高于常规单通道设备所观察到的电流水平。我们的结果表明，结合大量边缘的器件结构可以改善TMD FET的性能。这种改善归因于更高的局部电场，这是由边缘引起的，电荷载流子的有效数量增加，并且不存在任何与边缘相关的有害散射。

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