Most experiments on ultrafast magnetodynamics have been conducted using the magneto-optical Kerr effect. Here, we compare the Kerr effect's magnetic sensitivity to the spin dynamics measured by photoemission. The magnetization dynamics on an Fe/W(110) thin film are probed by spin-resolved photoemission spectroscopy and the Kerr effect. The results reveal similarities between the spin dynamics at low binding energy and the response probed by the Kerr effect. Therefore, the Kerr effect probes states relevant for spin transport and spin flips but may not be sensitive to the entire magnetic moment in femtosecond spin dynamics experiments.

中文翻译：

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超快磁性：磁光克尔效应和传导电子

大多数关于超快磁动力学的实验都是使用磁光克尔效应进行的。在这里，我们将克尔效应的磁灵敏度与通过光电发射测量的自旋动力学进行比较。Fe/W(110) 薄膜上的磁化动力学通过自旋分辨光电子能谱和克尔效应进行探测。结果揭示了低结合能下的自旋动力学与克尔效应探测的响应之间的相似性。因此，克尔效应探测与自旋输运和自旋翻转相关的状态，但可能对飞秒自旋动力学实验中的整个磁矩不敏感。