近日，复旦大学的吴义政&袁喆及其研究团队取得一项新进展。经过不懈努力，他们揭示由洛伦兹力诱导的金红石氧化膜中的反对称平面霍尔效应。相关研究成果已于2024年6月10日在国际知名学术期刊《科学通报》上发表。

本文报道了明确的实验观察，揭示了反对称平面霍尔效应（APHE）在中心对称的金红石RuO₂和IrO₂单晶薄膜中，相对于面内磁场的行为。实验发现，霍尔电阻率与沿特定晶体轴施加的面内磁场分量呈线性正比关系，这一现象与电流方向和温度无关。

实验观测结果与理论计算一致，证实了金红石氧化物薄膜中的APHE是由洛伦兹力引起的。这一研究发现可以推广到铁磁材料中，以发现反常霍尔效应和量子反常霍尔效应引起的面内磁化。除了极大丰富了霍尔效应的理论知识，本研究还为发掘霍尔效应家族中的新成员打开了大门。

据悉，传统的霍尔效应与垂直于薄膜的场分量或磁化分量成线性比例。尽管越来越多的理论提出了由贝里曲率引起的各种特殊系统的面内场或磁化的霍尔效应，但这种非常规的霍尔效应仅在Weyl半金属和异维超晶格中得到了实验报道。

附：英文原文

Title: Antisymmetric planar Hall effect in rutile oxide films induced by the Lorentz force

Author: Zhe Yuan b c, Yizheng Wu a h i

Issue&Volume: 2024/06/10

Abstract: The conventional Hall effect is linearly proportional to the field component or magnetization component perpendicular to a film. Despite the increasing theoretical proposals on the Hall effect to the in-plane field or magnetization in various special systems induced by the Berry curvature, such an unconventional Hall effect has only been experimentally reported in Weyl semimetals and in a heterodimensional superlattice. Here, we report an unambiguous experimental observation of the antisymmetric planar Hall effect (APHE) with respect to the in-plane magnetic field in centrosymmetric rutile RuO₂ and IrO₂ single-crystal films. The measured Hall resistivity is found to be linearly proportional to the component of the applied in-plane magnetic field along a particular crystal axis and to be independent of the current direction or temperature. Both the experimental observations and theoretical calculations confirm that the APHE in rutile oxide films is induced by the Lorentz force. Our findings can be generalized to ferromagnetic materials for the discovery of anomalous Hall effects and quantum anomalous Hall effects induced by in-plane magnetization. In addition to significantly expanding knowledge of the Hall effect, this work opens the door to explore new members in the Hall effect family.

DOI: 10.1016/j.scib.2024.06.009

Source: https://www.sciencedirect.com/science/article/abs/pii/S2095927324004055