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arXiv · 2110.03599

Ultrafast element- and depth-resolved magnetization dynamics probed by transverse magneto-optical Kerr effect spectroscopy in the soft x-ray range

Martin Hennecke·Daniel Schick·Themistoklis Sidiropoulos·Felix Willems·Anke Heilmann·Martin Bock·Lutz Ehrentraut·Dieter Engel·Piet Hessing·Bastian Pfau·Martin Schmidbauer·Andreas Furchner·Matthias Schnuerer·Clemens von Korff Schmising·Stefan Eisebitt
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Abstract

We report on time- and angle-resolved transverse magneto-optical Kerr effect spectroscopy in the soft x-ray range that, by analysis via polarization-dependent magnetic scattering simulations, allows us to determine the spatio-temporal and element-specific evolution of femtosecond laser-induced spin dynamics in nanostructured magnetic materials. In a ferrimagnetic GdFe thin film system, we correlate a reshaping spectrum of the magneto-optical Kerr signal to depth-dependent magnetization dynamics and disentangle contributions due to non-equilibrium electron transport and nanoscale heat diffusion on their intrinsic time scales. Our work provides a quantitative insight into light-driven spin dynamics occurring at buried interfaces of complex magnetic heterostructures, which can be tailored and functionalized for future opto-spintronic devices.

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Martin Hennecke, Daniel Schick, Themistoklis Sidiropoulos, Felix Willems, Anke Heilmann, Martin Bock, Lutz Ehrentraut, Dieter Engel, Piet Hessing, Bastian Pfau, Martin Schmidbauer, Andreas Furchner, Matthias Schnuerer, Clemens von Korff Schmising, Stefan Eisebitt. 2022-07-11. Ultrafast element- and depth-resolved magnetization dynamics probed by transverse magneto-optical Kerr effect spectroscopy in the soft x-ray range. https://doi.org/10.1103/physrevresearch.4.l022062

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