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arXiv · 1501.02895

Longitudinal evolution of magnetization of ferromagnets following ultrafast demagnetization: Role of finite size and shape of demagnetized region

I. A. Yastremsky
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Abstract

A dependence of a relaxation rate on the shape of the demagnetized region for a longitudinal evolution of total magnetization to its equilibrium value following the ultrafast demagnetization is demonstrated. This shape-dependence is caused by a motion of the wave front inside the demagnetized region. The contribution of the wave front for spherically symmetric shape of the demagnetized region is up to 3 times and for cylindrically symmetric shape up to 2 times stronger than for one dimensional demagnetized region. This effect can be observed after the demagnetization by a tightly focused femtosecond laser pulse.

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I. A. Yastremsky. 2015-01-13. Longitudinal evolution of magnetization of ferromagnets following ultrafast demagnetization: Role of finite size and shape of demagnetized region. https://doi.org/10.5488/cmp.17.44701

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