论文标题
通过扫描异常Nernst效果显微镜识别Mn $ _ {3} $ nin中的八杆抗磁性域取向
Identifying the octupole Antiferromagnetic domain orientation in Mn$_{3}$NiN by scanning Anomalous Nernst Effect microscopy
论文作者
论文摘要
磁性材料中的内在异常效应受费米能量下的浆果曲率控制，可以在具有消失的磁化化的非类别抗fiferromagnets中实现。 （001）面向的Mn $ _ {3} $ nin的薄膜具有其手性抗铁磁结构，位于（111）平面（111）平面，促进了异常的Nernst效应，异常的Nernst效应在两个正交的内置方向上异常。异常Nernst效应的每个成分的符号由局部抗磁磁性域状态确定。在这项工作中，通过重点扫描激光束在50 nm厚的Mn $ _ {3} $ nin两个微米大小的大厅交叉中诱导温度梯度，并使用异常的Nernst电压的空间分布来形象和识别八脑巨孔摩crododomain布置。尽管聚焦的激光束宽度可能跨越许多单个域，但在平面磁场中从室温从室温冷却到防铁磁过渡温度，可以使域状态制备产生棋盘格的域状态，这是由于每个域中的贡献。这些图像与原子和微磁模拟一起表明，平均大域的平均大域为$1μm^{2} $。
The intrinsic anomalous Nernst effect in a magnetic material is governed by the Berry curvature at the Fermi energy and can be realized in non-collinear antiferromagnets with vanishing magnetization. Thin films of (001)-oriented Mn$_{3}$NiN have their chiral antiferromagnetic structure located in the (111) plane facilitating the anomalous Nernst effect unusually in two orthogonal in-plane directions. The sign of each component of the anomalous Nernst effect is determined by the local antiferromagnetic domain state. In this work, a temperature gradient is induced in a 50 nm thick Mn$_{3}$NiN two micron-size Hall cross by a focused scanning laser beam, and the spatial distribution of the anomalous Nernst voltage is used to image and identify the octupole macrodomain arrangement. Although the focused laser beam width may span many individual domains, cooling from room temperature through the antiferromagnetic transition temperature in an in-plane magnetic field prepares the domain state producing a checkerboard pattern resulting from the convolution of contributions from each domain. These images together with atomistic and micromagnetic simulations suggest an average macrodomain of the order of $1 μm^{2}$.
