Investigation of Domains and Dynamics of Domain Walls by the Magneto‐optical Kerr‐effect
Investigation of Domains and Dynamics of Domain Walls by the Magneto‐optical Kerr‐effect
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通过磁光克尔效应研究磁畴和磁畴壁动力学
DOI：
10.1002/9780470022184.hmm310
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发表时间：
2007
影响因子：
4.6
通讯作者：
R. Schäfer
中科院分区：
文献类型：
--
作者：
R. Schäfer
克尔显微镜允许成像磁域和磁化过程在光学偏振显微镜。该方法基于磁光克尔效应，即平面偏振光的旋转与磁化方向与非透明样品反射的关系。通过分析仪，这种旋转被转换成（一般较弱的）可以通过数字图像处理增强的域对比度。克尔显微镜是最通用的区域成像方法，具有以下几个优点：(i)通过数字增强，几乎可以在所有种类的铁磁和铁磁材料上看到区域对比度。（ii）克尔效应对磁化矢量直接敏感，磁化矢量的方向也可以定量测量（至少在软磁材料中）。（iii）试样的尺寸和形状没有限制，在观察过程中可以很容易地对样品进行操作。（iv）可以施加任意磁场，以便实时观察成核和磁化过程。克尔显微镜提供了对动态过程进行高速观察的潜力。（六）金属的磁光信息深度约为10纳米。这使得在多层结构中对域进行单独成像成为可能。缺点是(i)横向分辨率有限，只有十分之一微米；（ii）对块状材料表面域成像的限制。在这篇文章中，克尔显微镜的领域和领域动力学的研究的可能性一起检讨与物理和技术基础。
Kerr microscopy allows to image magnetic domains and magnetization processes in an optical polarization microscope. The method is based on the magneto-optical Kerr effect, that is, the rotation of plane-polarized light in dependence of the magnetization direction on reflection from a nontransparent sample. By means of an analyzer, this rotation is converted into a (in general weak) domain contrast that can be enhanced by digital image processing. Kerr microscopy is the most versatile domain imaging method with several advantages: (i) By digital enhancement, domain contrast can be seen on virtually all kinds of ferro- and ferrimagnetic materials. (ii) The Kerr effect is directly sensitive to the magnetization vector whose direction can also quantitatively be measured (at least in soft magnetic materials). (iii) There is no restriction in specimen size and shape, and samples can easily be manipulated during observation. (iv) Arbitrary magnetic fields can be applied, so that nucleation and magnetization processes can be observed in real time. (v) Kerr microscopy offers the potential of high-speed observation of dynamic processes. (vi) The magneto-optical information depth is some 10 nm in metals. This makes it possible to separately image the domains in multilayer structures. Drawbacks are (i) a limited lateral resolution to some tenths of a micrometer and (ii) the restriction to the imaging of surface domains in bulk materials. In this article, the possibilities of Kerr microscopy for the investigation of domains and domain dynamics are reviewed together with physical and technological fundamentals.
Keywords:
magnetic domains;
magnetic microstructure;
magnetic imaging;
magnetization dynamics;
Kerr microscopy;
domain observation;
domain wall;
stroboscopic domain imaging