Scaling of the anomalous Hall effect in perpendicularly magnetized epitaxial films of the ferrimagnet NiCo2O4
Scaling of the anomalous Hall effect in perpendicularly magnetized epitaxial films of the ferrimagnet NiCo2O4
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DOI：
10.1103/physrevb.104.134407
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发表时间：
2021-10-11
影响因子：
3.7
通讯作者：
Shimakawa, Yuichi
中科院分区：
文献类型：
--
作者：
Kan, Daisuke;Xie, Lingling;Shimakawa, Yuichi
我们研究了垂直磁化的铁磁材料NiCo 2 O 4外延膜中的反常霍尔效应。我们发现反常霍尔电导率σ（AHE）与纵向电导率σ（xx）之间存在复杂的关系。当sigma（xx）相对较大（大于10（3）Ω（-1）cm（-1））时，sigma（AHE）几乎与sigma（xx）无关，但与磁化成比例。这种独特的标度行为的σ（AHE）表明，异常霍尔效应是由被占领的电子态的Berry曲率主导的内在起源。另一方面，当sigma（xx）降低时，标度关系改变为与sigma（1.6）（xx）类似的sigma（AHE），指示对sAHE的主导贡献从本征Berry相到杂质散射的交叉。结果表明，Berry曲率的本征贡献在NiCo 2 O 4薄膜的反常霍尔效应中起着至关重要的作用.
We investigate the anomalous Hall effect in perpendicularly magnetized ferrimagnet NiCo2O4 epitaxial films 3 to 30 nm thick. We find that the anomalous Hall conductivity sigma(AHE) has complex relations with the longitudinal electrical conductivity sigma(xx). When the sigma(xx) is relatively large (larger than 10(3) Omega(-1) cm(-1)), the sigma(AHE) is almost independent of the sigma(xx), but scales with the magnetization. This unique scaling behavior of sigma(AHE) indicates that the anomalous Hall effect is of intrinsic origin dominated by the Berry curvature of occupied electronic states. On the other hand, when the sigma(xx) is lowered, the scaling relation is changed to sigma(AHE) similar to sigma(1.6)(xx), indicating a crossover of the dominant contribution to sAHE, from the intrinsic Berry phase to the impurity scatterings. Our results show the intrinsic contribution from Berry curvature plays a crucial role in the anomalous Hall effect in NiCo2O4 films.