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arXiv · 1708.08919

Ultrafast hot-electron induced quenching of Tb4f magnetic order

T. Ferte·N. Bergeard·G. Malinowski·R. Abrudan·T. Kachel·K. Holldack·M. Hehn·C. Boeglin
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Abstract

We have investigated ultrafast quenching of the Tb4f magnetic order in Co74Tb26 alloys, induced by femtosecond hot-electrons pulses. The hot-electron pulses were produced in specific non-magnetic capping layers by infrared fs laser pulses. Our experimental results show that sub-picosecond dynamics of Tb4f magnetic moments can be induced by non-thermal and thermal hot-electrons. We further demonstrate that the demagnetization efficiencies of non-thermal and thermal hot electrons are similar. However, the characteristic demagnetization times show values of 0.35 ps for non-thermal hot-electrons excitations and 1.2 ps for thermal hot-electrons excitations. We explain this temporal elongation by the propagation time of thermal hot-electrons through the 15 nm thick CoTb film.

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T. Ferte, N. Bergeard, G. Malinowski, R. Abrudan, T. Kachel, K. Holldack, M. Hehn, C. Boeglin. 2017-08-31. Ultrafast hot-electron induced quenching of Tb4f magnetic order. https://doi.org/10.1103/physrevb.96.144427

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