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arXiv · 1412.0396

All-optical magnetization switching in ferrimagnetic alloys: deterministic vs thermally activated dynamics

L. Le Guyader·S. El Moussaoui·M. Buzzi·M. Savoini·A. Tsukamoto·A. Itoh·A. Kirilyuk·Th. Rasing·F. Nolting·A. V. Kimel
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Abstract

Using photo-emission electron microscopy with X-ray magnetic circular dichroism as a contrast mechanism, new insights into the all-optical magnetization switching (AOS) phenomenon in GdFe based rare-earth transition metal ferrimagnetic alloys are provided. From a sequence of static images taken after single linearly polarized laser pulse excitation, the repeatability of AOS can be measured with a correlation coefficient. It is found that low coercivity enables thermally activated domain wall motion, limiting in turn the repeatability of the switching. Time-resolved measurement of the magnetization dynamics reveal that while AOS occurs below and above the magnetization compensation temperature $T_\text{M}$, it is not observed in GdFe samples where $T_\text{M}$ is absent. Finally, AOS is experimentally demonstrated against an applied magnetic field of up to 180 mT.

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L. Le Guyader, S. El Moussaoui, M. Buzzi, M. Savoini, A. Tsukamoto, A. Itoh, A. Kirilyuk, Th. Rasing, F. Nolting, A. V. Kimel. 2014-12-01. All-optical magnetization switching in ferrimagnetic alloys: deterministic vs thermally activated dynamics. https://doi.org/10.1103/physrevb.93.134402

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