AI 中文总结
本文通过从头算研究揭示四声子过程使单层过渡金属二硫属化物2H相热导率额外降低15%-35%，而1Tp相几乎不受影响，两相热导率差异可用于设计热开关及声子逻辑元件。
AI 中文摘要
我们提出了一个全面的从头算研究，探讨高阶非谐性和多晶型现象对单层过渡金属二硫属化物晶格热导率κ的影响。我们证明，在基态2H相中，四声子过程导致κ额外降低15%至35%。相反，它们对热力学上具有竞争力的1Tp相的影响几乎可以忽略不计。2H高导热相与1Tp低导热相之间的κ差异可用于设计热开关，这些热开关可能在热管理和基于声子的逻辑元件开发中找到应用，特别是在碲化物的情况下，其中场控制的超快可逆相变已在实验中得到证实。
英文摘要
We present a comprehensive {\it ab initio} study of the effect of higher-order anharmonicity and polymorphism on the lattice thermal conductivity, ${\bm κ}$, of single-layer transition metal dichalcogenides. We show that four-phonon processes are responsible for an additional suppression of ${\bm κ}$ ranging from 15\% to 35\% in the ground-state 2H phase. Conversely, their effect is almost negligible on the thermodynamically competitive \1Tp\ phase. The ${\bm κ}$ difference between the 2H higher-conductivity phase and the \1Tp\ lower-conductivity phase can be exploited for the design of thermal switches that may find applications in thermal management and in the development of phonon-based logic elements, particularly in the case of tellurides, where field-controlled ultrafast and reversible phase transitions have already been demonstrated experimentally.
