Depth-resolved distribution of ultrafast spin currents and fluctuation in magnetic structures

我们建议利用超快XUV和软X射线磁反射率实验直接测量磁性多层膜样品中激光激发的自旋和电荷密度的超快空间演化。利用超短自由电子激光脉冲的相干特性，我们还利用共振磁X射线光子相关谱测量了自旋和电荷密度的时间涨落。这两个信息、自旋和电荷密度的时间演化以及它们各自的涨落将有助于揭开超快磁化动力学过程的微观细节。

We propose to directly measure the ultrafast spatial evolution of laser-excited spin and charge densities inside magnetic multilayer samples employing ultrafast XUV and soft X-ray magnetic reflectivity experiments at HHG and XFEL sources. Using the coherence properties of the ultra-short FEL pulses we also aim at measuring the temporal fluctuations of spin and charge densities by means of resonant magnetic X-ray photon correlation spectroscopy. Both information, the temporal evolution of the spin and charge densities and their respective fluctuations will help to unravel the microscopic details of processes involved in ultrafast magnetization dynamics.