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

oleh: 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

Format: Article
Diterbitkan: American Physical Society 2022-06-01

Deskripsi

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 spatiotemporal 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 nonequilibrium electron transport and nanoscale heat diffusion on their intrinsic timescales. Our Letter 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 optospintronic devices.