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arXiv · 2005.02872

Distinct Ultrafast Electronic and Magnetic Response in M-edge Magnetic Circular Dichroism

Kelvin Yao·Felix Willems·Clemens von Korff Schmising·Ilie Radu·Christian Strueber·Daniel Schick·Dieter Engel·Arata Tsukamoto·J. K. Dewhurst·Sangeeta Sharma·Stefan Eisebitt
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Abstract

Experimental investigations of ultrafast magnetization dynamics increasingly employ resonant magnetic spectroscopy in the ultraviolet spectral range. Besides allowing to disentangle the element-specific transient response of functional magnetic systems, these techniques also promise to access attosecond to few-femtosecond dynamics of spin excitations. Here, we report on a systematic study of transient magnetic circular dichroism (MCD) on the transition metals Fe, Co and Ni as well as on a FeNi and GdFe alloy and reveal a delayed onset between the electronic and magnetic response. Supported by \textit{ab-initio} calculations, we attribute our observation to a transient energy shift of the absorption and MCD spectra at the corresponding elemental resonances due to non-equilibrium changes of electron occupations.

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Kelvin Yao, Felix Willems, Clemens von Korff Schmising, Ilie Radu, Christian Strueber, Daniel Schick, Dieter Engel, Arata Tsukamoto, J. K. Dewhurst, Sangeeta Sharma, Stefan Eisebitt. 2020-05-06. Distinct Ultrafast Electronic and Magnetic Response in M-edge Magnetic Circular Dichroism. https://doi.org/10.1103/physrevb.102.100405

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