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Title: Superconducting properties in doped 2M-WS 2 from first principles
A new member of the transition metal dichalcogenide (TMD) family, 2M-WS 2, 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-WS 2 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.  more » « less
Award ID(s):
2035518
PAR ID:
10324965
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of Materials Chemistry C
ISSN:
2050-7526
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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