发表机构
Zhejiang University（浙江大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文建立非共线磁体中电子与磁振子的贝里曲率驱动非线性热霍尔效应理论，确定使三阶非线性热霍尔效应主导的对称性条件，以两种具体材料为例验证该效应，可用于诊断非共线磁性质并确定奈尔矢量取向。
AI 中文摘要
热霍尔效应（THE）是一种可用于探测材料性质的有力工具，即使是绝缘体也适用。本文通过建立由电子和磁振子的贝里曲率驱动的非线性THE理论，研究非共线磁体的热响应。我们确定了使三阶THE占主导、而线性和二阶贡献消失的对称性条件；具有面外奈尔序的d波和i波非共线磁体满足这些条件，而面内序则会产生占主导的线性THE。以KV₂Se₂O（一种d波非共线磁体金属）和MnF₂（一种非共线磁体绝缘体）为具体例子，我们分别证明了来自电子和磁振子的非零三阶非线性THE，二者均对温度梯度方向呈现π周期依赖关系。这些对称性保证的贝里曲率现象为候选材料中的非共线磁性质提供了诊断方法，并可用于确定奈尔矢量取向。
英文摘要
Thermal Hall effect (THE) is a powerful probe of material properties, even in insulators. Here we investigate the thermal response of altermagnets by developing a theory on Berry curvature driven nonlinear THE from both electrons and magnons. We identify symmetry conditions under which the third-order THE dominates while linear and second-order contributions vanish. Notably, d-wave and i-wave altermagnets with out-of-plane Neel order satisfy these conditions, whereas in-plane order yields a dominant linear THE. Using KV2Se2O (a d-wave altermagnetic metal) and MnF2 (an altermagnetic insulator) as concrete examples, we show nonzero third-order nonlinear THE from electrons and magnons, respectively, both exhibiting a pi-periodic dependence on the direction of temperature gradient. These symmetry-guaranteed Berry curvature phenomena provide a diagnostic for altermagnetism in candidate materials and enable determination of the Neel vector orientation.
Comments6 pages, 3 figures
