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arXiv · 1412.5396

Revealing the role of orbital magnetism in ultrafast laser-induced demagnetization in multisublattice metallic magnets by terahertz spectroscopy

T. J. Huisman·R. V. Mikhaylovskiy·A. Tsukamoto·Th. Rasing·A. V. Kimel
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Abstract

Simultaneous detection of THz emission and transient magneto-optical response is employed to study ultrafast laser-induced magnetization dynamics in multisublattice magnets NdFeCo and GdFeCo amorphous alloys with in-plane magnetic anisotropy. A satisfactory quantitative agreement between the dynamics revealed with the help of these two techniques is obtained for GdFeCo. For NdFeCo the THz emission reveals faster dynamics than the magneto-optical response. This indicates that in addition to spin dynamics of Fe ultrafast laser excitation triggers faster magnetization dynamics of Nd.

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T. J. Huisman, R. V. Mikhaylovskiy, A. Tsukamoto, Th. Rasing, A. V. Kimel. 2014-12-17. Revealing the role of orbital magnetism in ultrafast laser-induced demagnetization in multisublattice metallic magnets by terahertz spectroscopy. https://doi.org/10.1103/physrevb.92.104419

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