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arXiv · 0904.4399

Tracing the thermal mechanism in femtosecond spin dynamics

U. Atxitia·O. Chubykalo-Fesenko·J. Walowski·A. Mann·M. Munzenberg
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Abstract

We compare femtosecond pump-probe experiments in Ni and micromagnetic modelling based on the Landau-Lifshitz-Bloch equation coupled to a two-temperature model, revealing a predominant thermal ultrafast demagnetization mechanism. We show that both spin (femtosecond demagnetization) and electron-phonon (magnetization recovery) rates in Ni increase as a function of the laser pump fluence. The slowing down for high fluences arises from the increased longitudinal relaxation time.

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U. Atxitia, O. Chubykalo-Fesenko, J. Walowski, A. Mann, M. Munzenberg. 2009-04-28. Tracing the thermal mechanism in femtosecond spin dynamics. https://arxiv.org/abs/0904.4399

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