发表机构
State Key Laboratory of Surface Physics, and Department of Physics, Fudan University; Shanghai Research Center for Quantum Sciences; Center for Quantum Physics, Key Laboratory of Advanced Optoelectronic, Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology; Shanghai Branch, Hefei National Laboratory; Collaborative Innovation Center of Advanced Microstructures（复旦大学表面物理国家重点实验室及物理系; 上海量子科学研究中心; 北京理工大学物理学院先进光电量子架构与测量教育部重点实验室量子物理中心; 合肥国家实验室上海分部; 先进微结构协同创新中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究对无电荷密度波的 Ta 掺杂 kagome 金属 Cs(V0.86Ta0.14)3Sb5 开展高压实验，发现其存在压力诱导的双圆顶超导性，证实该特性是钒基 kagome 超导体的固有属性。
AI 中文摘要
钒基 kagome 超导体 CsV₃Sb₅ 呈现出电荷密度波（CDW）与超导性（SC）之间的复杂相互作用。用 Ta 替代 V 会抑制 CDW 序并增强超导性。在此，我们报道了对 Ta 掺杂的 Cs(V₀.₈₆Ta₀.₁₄)₃Sb₅ 开展的最高达 48 GPa 的高压研究，该样品的超导转变温度 Tc 约为 5.29 K，且无 CDW 序。在低压下，与纯 CsV₃Sb₅ 特征性的“M 形”温度-压力相图不同，Ta 掺杂化合物呈现出明显的非单调演化：初始时，Tc 从常压下的 5.29 K 略微下降至 0.33 GPa 时的 4.90 K，随后升高至 0.61 GPa 时的最大值 5.70 K；进一步压缩后，Tc 持续下降至 12.3 GPa 时的 0.98 K；在更高压力下，Tc 再次上升，在 47.7 GPa 时达到 4.46 K。这种 Tc 的演化在压力下形成了两个超导圆顶，与 CsV₃Sb₅ 中的情况类似。我们的结果表明，压力诱导的双圆顶超导性是这些钒基 kagome 超导体的固有特性，即使在不存在长程 CDW 序的情况下也是如此。
英文摘要
The vanadium-based kagome superconductor CsV$_3$Sb$_5$ exhibits an intricate interplay between charge density wave (CDW) and superconductivity (SC). Substituting Ta for V will suppress the CDW order and enhance superconductivity. Here, we report a high-pressure study up to 48 GPa on Ta-doped Cs(V$_{0.86}$Ta$_{0.14}$)$_3$Sb$_5$ with enhanced $T_\mathrm{c}$ around 5.29 K and without CDW order. At low pressures, unlike the characteristic $``$M-shaped" temperature-pressure phase diagram of the pristine CsV$_3$Sb$_5$, the Ta-doped compound exhibits a distinct non-monotonic evolution. Initially, $T_\mathrm{c}$ drops slightly from 5.29 K at ambient pressure to 4.90 K at 0.33 GPa, before increasing to a maximum of 5.70 K at 0.61 GPa. Upon further compression, $T_\mathrm{c}$ decreases continuously to 0.98 K at 12.3 GPa. At higher pressures, $T_\mathrm{c}$ rises again, reaching 4.46 K at 47.7 GPa. This evolution of $T_\mathrm{c}$ establishes two superconducting domes under pressure, which are similar to those in CsV$_3$Sb$_5$. Our results demonstrate that pressure-induced double-dome superconductivity is intrinsic to these V-based kagome superconductors, even in the absence of long-range CDW order.
Comments6 pages, 4 figures
