How strong correlations and topology interplay is a topic of great current interest. In this perspective paper, we focus on correlation-driven gapless phases. We take the time-reversal symmetric Weyl semimetal as an example because it is expected to have clear (albeit nonquantized) topological signatures in the Hall response and because the first strongly correlated representative, the noncentrosymmetric Weyl–Kondo semimetal Ce₃Bi₄Pd₃, has recently been discovered. We summarize its key characteristics and use them to construct a prototype Weyl–Kondo semimetal temperature-magnetic field phase diagram. This allows for a substantiated assessment of other Weyl–Kondo semimetal candidate materials. We also put forward scaling plots of the intrinsic Berry-curvature-induced Hall response vs the inverse Weyl velocity—a measure of correlation strength, and vs the inverse charge carrier concentration—a measure of the proximity of Weyl nodes to the Fermi level. They suggest that the topological Hall response is maximized by strong correlations and small carrier concentrations. We hope that our work will guide the search for new Weyl–Kondo semimetals and correlated topological semimetals in general, and also trigger new theoretical work.

中文翻译：

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如何识别和表征强相关拓扑半金属


相关性和拓扑相互作用的强弱是当前人们非常感兴趣的话题。在这篇展望论文中，我们重点关注相关驱动的无间隙阶段。我们以时间反演对称Weyl半金属为例，因为它预计在霍尔响应中具有清晰的（尽管非量化的）拓扑特征，并且因为第一个强相关代表，非中心对称Weyl-Kondo半金属Ce ₃ Bi ₄ Pd ₃ ，最近被发现。我们总结了它的关键特征，并用它们构建了原型 Weyl-Kondo 半金属温度-磁场相图。这可以对其他 Weyl-Kondo 半金属候选材料进行实质性评估。我们还提出了本征贝里曲率引起的霍尔响应与逆韦尔速度（相关强度的度量）和逆电荷载流子浓度（衡量韦尔节点与费米能级接近程度的度量）的比例图。他们认为，强相关性和小载流子浓度可以使拓扑霍尔响应最大化。我们希望我们的工作能够指导新的 Weyl-Kondo 半金属和相关拓扑半金属的研究，并引发新的理论工作。