Effect of substitution on the superconducting phase of transition metal dichalcogenide Nb(Se[Formula: see text]S[Formula: see text])[Formula: see text] van der Waals layered structure

Prutthipong Tsuppayakorn-Aek; Prayoonsak Pluengphon; Piya Phansuke; Burapat Inceesungvorn; Wutthikrai Busayaporn; Pungtip Kaewtubtim; Thiti Bovornratanaraks

doi:10.1038/s41598-021-94000-2

Effect of substitution on the superconducting phase of transition metal dichalcogenide Nb(Se[Formula: see text]S[Formula: see text])[Formula: see text] van der Waals layered structure

Sci Rep. 2021 Jul 26;11(1):15215. doi: 10.1038/s41598-021-94000-2.

Authors

Prutthipong Tsuppayakorn-Aek^{1

2}, Prayoonsak Pluengphon³, Piya Phansuke⁴, Burapat Inceesungvorn⁵, Wutthikrai Busayaporn⁶, Pungtip Kaewtubtim⁴, Thiti Bovornratanaraks^{1

2}

Affiliations

¹ Extreme Conditions Physics Research Laboratory (ECPRL) and Physics of Energy Materials Research Unit, Department of Physics, Faculty of Science, Chulalongkorn University, Bangkok, 10330 Thailand.
² Thailand Centre of Excellence in Physics, Ministry of Higher Education, Science, Research and Innovation, 328 Si Ayutthaya Road, Bangkok, 10400 Thailand.
³ Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, 10540 Thailand.
⁴ Department of Science, Faculty of Science and Technology, Prince of Songkla University, Pattani Campus, Pattani, 94000 Thailand.
⁵ Department of Chemistry, Center of Excellence in Materials Science and Technology and Materials Science Research Centre, Faculty of Science, Chiang Mai University, Chiang Mai, 50200 Thailand.
⁶ Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, 30000 Thailand.

Abstract

By means of first-principles cluster expansion, anisotropic superconductivity in the transition metal dichalcogenide Nb(Se[Formula: see text]S[Formula: see text])[Formula: see text] forming a van der Waals (vdW) layered structure is observed theoretically. We show that the Nb(Se[Formula: see text]S[Formula: see text])[Formula: see text] vdW-layered structure exhibits minimum ground-state energy. The Pnnm structure is more thermodynamically stable when compared to the 2H-NbSe[Formula: see text] and 2H-NbS[Formula: see text] structures. The characteristics of its phonon dispersions confirm its dynamical stability. According to electronic properties, i.e., electronic band structure, density of states, and Fermi surface indicate metallicity of Nb(Se[Formula: see text]S[Formula: see text])[Formula: see text]. The corresponding superconductivity is then investigated through the Eliashberg spectral function, which gives rise to a superconducting transition temperature of 14.5 K. This proposes a remarkable improvement of superconductivity in this transition metal dichalcogenide.