Emergence of Phonon‐Mediated Superconductivity in Electron‐Doped Monolayer WS2: First‐Principles Study

Abstract

Herein, the electronic properties for undoped and carrier‐doped tungsten disulfide (WS2) monolayer are systematically examined by using ab initio calculations. The results show that the pristine single‐layer WS2 is a semiconductor with a direct bandgap nature and the electronic properties of WS2 are similar to 2H‐MoS2 monolayer, which are consistent with previous reports. Besides, considerable changes are observed in the electron‐doped WS2 monolayer when compared to the hole‐doped. The dynamical stability of pristine and carrier‐doped WS2 monolayer is also investigated by performing the phonon dispersion calculations. Further, the possibility of superconducting nature in carrier‐doped single‐layer WS2 is also studied by using the isotropic Migdal–Eliashberg theory with the combination of Wannier–Fourier interpolation. From the computed Eliashberg function, it has been concluded that electron doping to WS2 monolayer promises electron–phonon coupling strength and maximum critical temperature of around 17 K with doping concentration ranging from 0.4 to 0.16 electrons cell−1.