Janus transition metal-dichalcogenide materials have attracted a great deal of attention due to their remarkable physical properties arising from the two-dimensional geometry and the breakdown of the out-of-plane symmetry. Using first-principles density functional theory, we investigated the phase stability, strain-enhanced phase stability, and superconductivity of Janus WSeH and WSH. In addition, we investigated the contribution of the phonon linewidths from the phonon energy spectrum responsible for the superconductivity and the electron-phonon coupling as a function of phonon wave vectors and modes. Previous work has examined hexagonal 2H and tetragonal 1T structures, but we found that neither is a ground-state structure. The metastable 2H phase of WSeH is dynamically stable with T𝑐≈11.60K, similar to WSH. Compressive biaxial strain—the two-dimensional equivalent of pressure—can stabilize the 1T structures of WSeH and WSH with T𝑐≈9.23K and 10.52 K, respectively.

中文翻译：

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Janus 钨硫属化物氢化物单层的超导性和应变增强相稳定性


Janus 过渡金属-硫化物材料因其二维几何形状和面外对称性的破坏而引起的显着物理性能而受到广泛关注。使用第一性原理密度泛函理论，我们研究了 Janus WSeH 和 WSH 的相稳定性、应变增强相稳定性和超导性。此外，我们还研究了负责超导的声子能谱中的声子线宽和电子-声子耦合作为声子波矢量和模式的函数的贡献。以前的工作检查了六边形 2H 和四边形 1T 结构，但我们发现两者都不是基态结构。WSeH 的亚稳态 2H 期与 Tc≈11.60K 动态稳定，类似于 WSH。压缩双轴应变（压力的二维等效物）可以分别用 Tc≈9.23K 和 10.52 K 稳定 WSeH 和 WSH 的 1T 结构。