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arXiv · 0803.3686

Unusual spin-wave population in nickel after femtosecond laser pulse excitation

Benjamin Lenk·Gerrit Eilers·Jaroslav Hamrle·Markus Münzenberg
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Abstract

The spin-wave relaxation mechanisms after intense laser excitation in ferromagnetic nickel films are investigated with all-optical pump-probe experiments. Uniform precession (Kittel mode), Damon-Eshbach surface modes and perpendicular standing spin waves can be identified by their dispersion f(H). However, different to other ferromagnets f(H) deviates from the expected behavior. Namely, a mode discontinuity is observed, that can be attributed to a non-linear process. Above a critical field the power spectrum reveals a redistribution of the energy within the spin-wave spectrum populated.

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Benjamin Lenk, Gerrit Eilers, Jaroslav Hamrle, Markus Münzenberg. 2010-06-22. Unusual spin-wave population in nickel after femtosecond laser pulse excitation. https://doi.org/10.1103/physrevb.82.134443

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