Title: Suppression of both superconductivity and structural transition in hole-doped MoTe$_2$ induced by Ta substitution Show Chinese title

Title: 空穴掺杂MoTe$_2$中由Ta取代引起的超导性和结构相变的抑制

Abstract: Type-II Weyl semimetal MoTe$_2$ exhibits a first-order structural transition at $T_s$ $\sim$250~K and superconducts at $T_c$ $\sim$0.1~K at ambient pressure. Both $T_s$ and $T_c$ can be manipulated by several tuning parameters, such as hydrostatic pressure and chemical substitution. It is often reported that suppressing $T_s$ enhances $T_c$, but our study shows a different behaviour when MoTe$_2$ is hole-doped by Ta. When $T_s$ is suppressed by Ta doping, $T_c$ is also suppressed. Our findings suggest that the suppression of $T_s$ does not necessarily enhance superconductivity in MoTe$_2$. By connecting with the findings of electron-doped MoTe$_2$, we argue that varying electron carrier concentration can effectively tune $T_c$. In addition, the Hall coefficient is enhanced around the doping region, where $T_s$ is completely suppressed, suggesting that the critical scattering around the structural transition may also play a role in suppressing $T_c$. Show Chinese abstract

Abstract: Type-II Weyl semimetal MoTe$_2$ exhibits a first-order structural transition at $T_s$ $\sim$ 250~K and superconducts at $T_c$ $\sim$ 0.1~K at ambient pressure. Both $T_s$ and $T_c$ can be manipulated by several tuning parameters, such as hydrostatic pressure and chemical substitution. 经常有报道指出，抑制$T_s$会增强$T_c$，但我们的研究表明，当 MoTe$_2$通过 Ta 掺杂进行空穴掺杂时，表现出不同的行为。 当$T_s$被 Ta 掺杂抑制时，$T_c$也被抑制。 我们的研究结果表明，$T_s$的抑制并不一定增强 MoTe$_2$中的超导性。 通过与电子掺杂 MoTe$_2$的研究结果相结合，我们认为改变电子载流子浓度可以有效调节$T_c$。 此外，在掺杂区域附近霍尔系数增强，其中$T_s$完全被抑制，这表明结构相变附近的临界散射也可能在抑制$T_c$中起到作用。