The mechanisms of carrier transport in the cross‐plane crystal orientation of transition metal dichalcogenides are examined. The study of in‐plane electronic properties of these van der Waals compounds has been the main research focus in recent years. However, the distinctive physical anisotropies, short‐channel physics, and tunability of cross layer interactions can make the study of their electronic properties along the out‐of‐plane crystal orientation valuable. Here, the out‐of‐plane carrier transport mechanisms in niobium diselenide and hafnium disulfide are explored as two broadly different representative materials. Temperature‐dependent current–voltage measurements are preformed to examine the mechanisms involved. First principles simulations and a tunneling model are used to understand these results and quantify the barrier height and hopping distance properties. Using Raman spectroscopy, the thermal response of the chemical bonds is directly explored and the insight into the van der Waals gap properties is acquired. These results indicate that the distinct cross‐plane carrier transport characteristics of the two materials are a result of material thermal properties and thermally mediated transport of carriers through the van der Waals gaps. Exploring the cross‐plane electron transport, the exciting physics involved is unraveled and potential new avenues for the electronic applications of van der Waals layers are inspired.

中文翻译：

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范德华分层材料中的跨平面载运

考察了过渡金属二卤化物在跨平面晶体取向中的载流子传输机理。这些范德华化合物的面内电子性质的研究已成为近年来的主要研究重点。但是，独特的物理各向异性，短通道物理特性和跨层相互作用的可调谐性，使得沿着平面外晶体取向研究其电子特性非常有价值。在此，探讨了硒化二铌和二硫化ha中的面外载流子传输机制，作为两种截然不同的代表性材料。执行取决于温度的电流-电压测量以检查所涉及的机制。第一性原理模拟和隧穿模型用于理解这些结果并量化势垒高度和跳变距离属性。使用拉曼光谱法，直接探索了化学键的热响应，并获得了对范德华间隙性质的见解。这些结果表明，两种材料截然不同的跨平面载流子传输特性是材料热性质和通过范德华间隙通过热介导的载流子传输的结果。探索跨平面电子传输，揭示了令人兴奋的物理原理，并激发了范德华层电子应用的潜在新途径。直接研究化学键的热响应，并获得对范德华间隙性质的见解。这些结果表明，两种材料截然不同的跨平面载流子传输特性是材料热性质和通过范德华间隙通过热介导的载流子传输的结果。探索跨平面电子传输，揭示了令人兴奋的物理原理，并激发了范德华层电子应用的潜在新途径。直接研究化学键的热响应，并获得对范德华间隙性质的见解。这些结果表明，两种材料截然不同的跨平面载流子传输特性是材料热性质和通过范德华间隙通过热介导的载流子传输的结果。探索跨平面电子传输，揭示了令人兴奋的物理原理，并激发了范德华层电子应用的潜在新途径。