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arXiv · 2211.01230

Pump--probe x-ray microscopy of photo-induced magnetization dynamics at MHz repetition rates

Kathinka Gerlinger·Bastian Pfau·Martin Hennecke·Lisa-Marie Kern·Ingo Will·Tino Noll·Markus Weigand·Joachim Gräfe·Nick Träger·Michael Schneider·Christian M. Günther·Dieter Engel·Gisela Schütz·Stefan Eisebitt
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Abstract

We present time-resolved scanning x-ray microscopy measurements with picosecond photo-excitation via a tailored infrared pump laser at a scanning transmission x-ray microscope. Specifically, we image the laser-induced demagnetization and remagnetization of thin ferrimagnetic GdFe films proceeding on a few nanoseconds time scale. Controlling the heat load on the sample via additional reflector and heat-sink layers allows us to conduct destruction-free measurements at a repetition rate of \SI{50}{\mega\hertz}. Near-field enhancement of the photo-excitation and controlled annealing effects lead to laterally heterogeneous magnetization dynamics which we trace with \SI{30}{\nano\meter} spatial resolution. Our work opens new opportunities to study photo-induced dynamics on the nanometer scale, with access to picosecond to nanosecond timescales, which is of technological relevance, especially in the field of magnetism.

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Kathinka Gerlinger, Bastian Pfau, Martin Hennecke, Lisa-Marie Kern, Ingo Will, Tino Noll, Markus Weigand, Joachim Gräfe, Nick Träger, Michael Schneider, Christian M. Günther, Dieter Engel, Gisela Schütz, Stefan Eisebitt. 2022-11-02. Pump--probe x-ray microscopy of photo-induced magnetization dynamics at MHz repetition rates. https://doi.org/10.1063/4.0000167

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