Stroboscopic domain imaging by Kerr microscopy

结构化磁膜系统的再磁化过程，因为它们目前被开发用于磁存储器和传感器应用，通过在微米尺寸范围和更大范围内的元素的复杂的磁畴状态进行。在该项目中要解决的主题是在脉冲磁场的应用下，在横向尺寸为几微米到十几微米的单层和多层膜元件中的磁化的快速反转。动态发展的领域将直接观察到的时间分辨宽场克尔显微镜的时间分辨率约为100皮秒在最高的横向分辨率可能在光学。一个超快的CCD相机连同一个恒定的光源将用于成像。由于弱克尔对比度，需要在频闪平均技术中积累图像以获得足够的信噪比。因此，该方法限于重复磁化模式。我们的显微镜结合了数字增强克尔显微镜的优势和高速观察的可能性。

The remagnetization process of structured magnetic film systems, as they are currently developed for magnetic memory and sensor applications, proceeds by complicated domain states for elements in the micrometer size range and beyond. The topic to be addressed in the project is the fast reversal of magnetization in single and multilayer film elements with lateral dimensions of a few micrometers up to some ten micrometers upon the application of pulsed magnetic fields. The dynamic development of domains will be directly observed by time-resolved widefield Kerr microscopy with a time resolution of about 100 picoseconds at highest lateral resolution possible in optics. An ultrafast CCD camera together with a constant light source will be used for imaging. Due to the weak Kerr contrast, an accumulation of images in a stroboscopic averaging technique is required to get sufficient signal-to-noise ratios. Therefore the method is restricted to repetitive magnetization modes. Our microscope combines the advantage of digitally enhanced Kerr microscopy with the possibility of high-speed observation.