The classical and quantum Hall effects are important subjects in condensed matter physics. The emergent 3D quantum Hall effects and nonlinear Hall effect have attracted considerable interest recently, with the former elevating the quantum Hall effect to a higher dimension and the latter extending the Hall effect to higher-order responses. In this perspective, we briefly introduce these two new members of the Hall family and discuss the open questions and future research directions.

中文翻译：

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3D 量子霍尔效应和非线性霍尔效应

经典和量子霍尔效应是凝聚态物理中的重要课题。新兴的 3D 量子霍尔效应和非线性霍尔效应最近引起了相当大的兴趣，前者将量子霍尔效应提升到更高维度，后者将霍尔效应扩展到更高阶响应。从这个角度，我们简要介绍了霍尔家族的这两个新成员，并讨论了未解决的问题和未来的研究方向。