论文标题
垂直磁各向异性的起源
Origin of Perpendicular Magnetic Anisotropy in Co$_x$Fe$_{3-x}$O$_{4+δ}$ Thin Films Studied by X-ray Magnetic Circular and Linear Dichroisms
论文作者
论文摘要
我们研究了特定元素特异性的自旋和轨道状态及其在共晶中的磁各向异性上的作用（Co $ _x $ _x $ fe $ _ {3-x} $ o $ $ $ _ {4+δ} $（001））薄膜，这些薄膜表现出垂直磁性磁性anisotropy（PMA）。 PMA在低$ x $区域中的起源（$ x $ <$ <$ 1）可以主要由Co $^{2+} $（3 $ d^7 $）的大型垂直轨道磁矩（3 $ d^7 $）在X射线磁性循环循环和线性Dichroism（XMCD/XMLD）中。具有方形磁滞曲线的PMA膜（$ x = 0.2 $）的XMLD显示了Co $^{2+} $位点中的扁平电荷分布，这与通过扩展X射线吸收吸收良好结构分析检测到的CO中局部最近的邻居距离的变化是一致的。我们的发现表明，共晶中PMA的显微镜起源来自沿平面外[001]方向增强的轨道磁矩，通过拉伸菌株通过平面电荷分布，从应变和轨道磁性磁力的观点中增加了尖晶石铁矿薄膜中的材料功能。
We investigate the element-specific spin and orbital states and their roles on magnetic anisotropy in the Co-ferrite (Co$_x$Fe$_{3-x}$O$_{4+δ}$ (001)) thin films which exhibit perpendicular magnetic anisotropy (PMA). The origin of PMA in the low $x$ region ($x$ $<$ 1) can be mainly explained by the large perpendicular orbital magnetic moments in the Co$^{2+}$ (3$d^7$) states detected by X-ray magnetic circular and linear dichroisms (XMCD/XMLD). The XMLD for a PMA film ($x=0.2$) with square hysteresis curve shows the oblate charge distribution in the Co$^{2+}$ site, which is consistent with the change in local nearest neighbor distance in Co detected by extended X-ray absorption fine structure analysis. Our finding reveals that the microscopic origin of PMA in Co-ferrite comes from the enhanced orbital magnetic moments along out-of-plane [001] direction through in-plane charge distribution by tensile strain, which adds the material functionalities in spinel ferrite thin films from the viewpoint of strain and orbital magnetic moments.
