Superconducting properties in doped 2M-WS 2 from first principles
Superconducting properties in doped 2M-WS 2 from first principles
复制标题
根据第一原理研究掺杂 2M-WS 2 的超导特性
DOI：
10.1039/d2tc01173e
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发表时间：
2022
影响因子：
6.4
通讯作者：
Margine, Elena R.
中科院分区：
文献类型：
--
作者：
Paudyal, Hari;Margine, Elena R.
过渡金属二卤化物(TMD)家族中的一个新成员2M-WS2最近被发现并表现出超导电性，其临界温度(T_C)为8.8K，是常压超导TMD中T_c最高的。利用第一性原理计算并结合Migdal-Eliashberg公式，我们探索了如何通过掺杂来提高2M-WS2的超导性质。在W位使用Mo、Nb和Ta，而在S位使用Se。我们证明了实验观察到的Mo和Se掺杂T_c的单调下降是由于费米能级的态密度降低和低能声子的电子-声子耦合。此外，我们还发现当Nb和Ta掺杂时，电子-声子耦合显著增加，导致T_c比未掺杂化合物提高了50%。
A new member of the transition metal dichalcogenide (TMD) family, 2M-WS2, has been recently discovered and shown to display superconductivity with a critical temperature (Tc) of 8.8 K, the highest Tc among superconducting TMDs at ambient pressure. Using first-principles calculations combined with the Migdal-Eliashberg formalism, we explore how the superconducting properties of 2M-WS2 can be enhanced through doping. Mo, Nb, and Ta are used as dopants at the W sites, while Se is used at the S sites. We demonstrate that the monotonous decrease in the Tc observed experimentally for Mo and Se doping is due to the decrease in density of states at the Fermi level and the electron–phonon coupling of the low-energy phonons. In addition, we find that a noticeable increase in the electron–phonon coupling could be achieved when doping with Nb and Ta, leading to an enhancement of the Tc of up to 50% compared to the undoped compound.