Two-dimensional transition-metal dichalcogenide (TMDs) MoTe2 has attracted much attention due to its predicted Weyl semimetal state and a quantum spin Hall insulator in bulk and monolayer form, respectively. We find that the superconductivity in MoTe2 single crystal can be greatly enhanced by the partial substitution of the Te ions by the S ones. The maximum superconducting temperature TC of MoTe1.8S0.2 single crystal is about 1.3 K. Compared with the parent MoTe2 single crystal (TC = 0.1 K), nearly 13-fold in TC is improved in the MoTe1.8S0.2 one. The superconductivity has been investigated through the resistivity and magnetization measurements. MoTe2−xSx single crystals belong to weak coupling superconductors and the improvement of the superconductivity may be related to the enhanced electron-phonon coupling induced by the S-ion substitution. A dome-shaped superconducting phase diagram is obtained in the S-doped MoTe2 single crystals. MoTe2−xSx materials may provide a new platform for our understanding of superconductivity phenomena and topological physics in TMDs.

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See supplementary material at http://dx.doi.org/10.1063/1.4947433 for experiment details, structural information, sample characterization and calculated details.

Supplementary Material

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