Enhanced superconductivity with interlayer spacing dependent T c in intercalated Weyl semimetal MoTe 2

Abstract Manipulating the strength of the interlayer coupling is an effective strategy to induce intriguing properties in layered materials. Recently, enhanced superconductivity has been reported in Weyl semimetal MoTe 2 and WTe 2 via ionic liquid (IL) cation intercalation. However, how the superconductivity enhancement depends on the interlayer interaction still remains elusive. Here by inserting IL cations with different sizes into MoTe 2 through this strategy, we are able to tune the interlayer spacing of the intercalated MoTe 2 samples and reveal the dependence of superconducting transition temperature T c on the interlayer spacing. Our results show that T c increases with the interlayer spacing, suggesting that the weakened interlayer coupling plays an important role in the superconductivity. Interestingly, the intercalation induced superconductivity shows a high Ginzburg–Landau anisotropy, which suggests a quasi-two-dimensional nature of the superconductivity where the adjacent superconducting layers are coupled through Josephson tunnelling.