Magnetization Dynamics and magnetic microscopy on the picosecond timescale

我们将研究微米级磁性元件和延伸膜在快上升时间磁场脉冲激励下的磁化响应。研究将使用时间分辨扫描克尔显微镜，时间分辨率约为1ps，空间分辨率约为0.3-1微米。快速上升时间场脉冲将触发磁化的进动，这将被本地记录。通过这种方式，我们获得了皮秒时间尺度上非均匀磁化激发的信息。这些实验可以在空气和超高真空中进行，这使得我们能够研究干净的外延生长的单晶磁层。此外，微米级的磁性元件可以在原位生长。将特别强调在这些清洁样品中的阻尼参数的演变。此外，还将研究快磁场脉冲激励下的交换耦合铁磁层。

We will study the response of the magnetization of micron sized magnetic elements and extended films when they are excited by fast rise time magnetic field pulses. Investigations will utilize a time resolved scanning Kerr microscope with temporal resolution of about 1 ps and spatial resolution of 0.3 - 1 micron. The fast rise time field pulses will trigger the precessional motion of the magnetization which will be recorded locally. In this way, we gain information on non-uniform magnetization excitations on the picosecond time-scale. The experiments can be performed in air and in ultra high vacuum which allows us to investigate clean epitaxially grown single crystalline magnetic layers. In addition, micron sized magnetic elements can be grown in-situ. Special emphasis will be given to the evolution of the damping parameter in these clean samples. In addition, exchange coupled ferromagnetic layers will be studied when excited by a fast magnetic field pulse.