Tunable structural phase transition and superconductivity in the Weyl semimetal <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="normal">Mo</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>−</mml:mo><mml:mi>x</mml:mi></mml:mrow></mml:msub><mml:msub><mml:mi mathvariant="normal">W</mml:mi><mml:mi>x</mml:mi></mml:msub><mml:msub><mml:mi mathvariant="normal">Te</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>
Rabin Dahal, Liangzi Deng, Narayan Poudel, Melissa Gooch, Zheng Wu, Hung‐Cheng Wu, H. D. Yang, Chung‐Kai Chang, C. W. Chu
Abstract
The relationship among structural transition, superconductivity, and doping in the Weyl semimetal ${\mathrm{Mo}}_{1\ensuremath{-}x}{\mathrm{W}}_{x}{\mathrm{Te}}_{2}$ has been established through a systematic study of the doping and pressure effects. Doping-dependent resistivity measurements at ambient pressure revealed that the structural transition temperature increases linearly with increasing W content in ${\mathrm{Mo}}_{1\ensuremath{-}x}{\mathrm{W}}_{x}{\mathrm{Te}}_{2}$. The observed structural transition temperature $({T}_{s})$ of ${\mathrm{MoTe}}_{2}$ at ambient pressure is 249 K and that of ${\mathrm{WTe}}_{2}$ is 613 K. Temperature-dependent synchrotron x-ray diffraction measurements further confirmed the structural transition in ${\mathrm{WTe}}_{2}$ at ambient pressure. Pressure was found to continuously suppress the ${T}_{s}$ in ${\mathrm{Mo}}_{0.90}{\mathrm{W}}_{0.10}{\mathrm{Te}}_{2},{\mathrm{Mo}}_{0.60}{\mathrm{W}}_{0.40}{\mathrm{Te}}_{2}$, and ${\mathrm{Mo}}_{0.25}{\mathrm{W}}_{0.75}{\mathrm{Te}}_{2}$, and superconductivity emerges in ${\mathrm{Mo}}_{0.90}{\mathrm{W}}_{0.10}{\mathrm{Te}}_{2}$ and ${\mathrm{Mo}}_{0.60}{\mathrm{W}}_{0.40}{\mathrm{Te}}_{2}$ above 1.25 K when ${T}_{s}$ is suppressed to a lower temperature.