Tunable phase transition and superconductivity in the Weyl semimetal Mo_1-xW_xTe₂

Weyl semimetals research has been slower than desired for many years due to the lack of experimentally feasible candidate materials. While transition-metal chalcogenides have been theoretically predicted, new Weyl semimetals are being experimentally discovered. One example is WTe_2, which has recently attracted significant interest due to its very large, non-saturating magnetoresistance up to 60 T and pressure-induced superconductivity. From this discovery, a tunable Weyl state in Mo_xW_1-xTe₂ was then proposed. Our group systematically investigated Mo_xW_1-xTe₂ single crystals in terms of their doping-dependent magnetotransport properties, phase transitions, and high-pressure effects. A phase diagram under pressure up to 43 GPa was constructed. With an increase in pressure, the magnetoresistance of Mo_0.5W_0.5Te₂ is suppressed, its Hall coefficient changes sign, and superconductivity emerges, suggesting a significant reconstruction of the Fermi surface. The T_c-P phase diagram shows dome-shaped superconducting behavior in Mo_0.5W_0.5Te₂. Theoretical analysis will also be discussed.