论文标题
铁磁性MN $ _4 $ n电影中的异常大厅和Nernst效果：可能的解释和增强前景
Anomalous Hall and Nernst effects in ferrimagnetic Mn$_4$N films: possible interpretation and prospect for enhancement
论文作者
论文摘要
铁磁Mn $ _4 $ N是基于异常Nernst效果（ANE）的热通量传感器的有前途的材料，因为其单轴磁性相当可观（$ k _ {\ rm u} $）和低饱和度磁化值（$ k _ {\ rm u} $）和低饱和度磁化（$ m_ _ {$ m_ _ {\ rm s} $）。我们在溅射沉积的Mn $ _4 $ N电影中对ANE和异常大厅的效应进行了实验和理论研究。据透露，观察到的负面异常的霍尔电导率（$σ_{xy} $）可以通过两个不同的共存磁性结构来解释，即具有高$ k _ {\ rm u} $污染的主要磁性结构，该结构被另一个结构污染的，具有$ k _ {\ rm u} $ u} $ nibt for -n offic for to to n offect for to n offect，观察到的$+0.5 \，μ{\ rm v/k} $ $ 300 \，{\ rm k} $的观察到的横向热电功率（$ s {\ rm ane} $）为$+0.5 \，μ{\ rm v/k} $，给出了横向热电系数（$α_{xy a} $ $+++++++++++0.34 {mm， k）} $，它小于第一原理计算所预测的值。基于第一原则计算的$α_{xy} $的解释使我们得出结论，结论是，具有高$ k _ {\ rm u} $的单个磁性结构的实现以及费米级的最佳调整是有希望的方法，可以增强$ s _ {\ rm and $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n $ n。 $α_{xy} $的放大到理论值$ 1.77 \，{\ rm a/（m \ cdot k）} $。
Ferrimagnetic Mn$_4$N is a promising material for heat flux sensors based on the anomalous Nernst effect (ANE) because of its sizable uniaxial magnetic anisotropy ($K_{\rm u}$) and low saturation magnetization ($M_{\rm s}$). We experimentally and theoretically investigated the ANE and anomalous Hall effect in sputter-deposited Mn$_4$N films. It was revealed that the observed negative anomalous Hall conductivity ($σ_{xy}$) could be explained by two different coexisting magnetic structures, that is, a dominant magnetic structure with high $K_{\rm u}$ contaminated by another structure with negligible $K_{\rm u}$ owing to an imperfect degree of order of nitrogen. The observed transverse thermoelectric power ($S_{\rm ANE}$) of $+0.5\, μ{\rm V/K}$ at $300\, {\rm K}$ gave a transverse thermoelectric coefficient ($α_{xy}$) of $+0.34\, {\rm A/(m \cdot K)}$, which was smaller than the value predicted from first-principles calculation. The interpretation for $α_{xy}$ based on the first-principles calculations led us to conclude that the realization of single magnetic structure with high $K_{\rm u}$ and optimal adjustment of the Fermi level are promising approaches to enhance $S_{\rm ANE}$ in Mn$_4$N through the sign reversal of $σ_{xy}$ and the enlargement of $α_{xy}$ up to a theoretical value of $1.77\, {\rm A/(m \cdot K)}$.
