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arXiv · 1103.1997

Suppression of Standing Spin Waves in Low-Dimensional Ferromagnets

Andrea Taroni·Anders Bergman·Lars Bergqvist·Johan Hellsvik·Olle Eriksson
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Abstract

We examine the experimental absence of standing spin wave modes in thin magnetic films, by means of atomistic spin dynamics simulations. Using Co on Cu(001) as a model system, we demonstrate that by increasing the number of layers, the "optical" branches predicted from adiabatic first-principles calculations are strongly suppressed, in agreement with spin-polarized electron energy loss spectroscopy measurements reported in the literature. Our results suggest that a dynamical analysis of the Heisenberg model is sufficient in order to capture the strong damping of the standing modes.

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Andrea Taroni, Anders Bergman, Lars Bergqvist, Johan Hellsvik, Olle Eriksson. 2011-05-23. Suppression of Standing Spin Waves in Low-Dimensional Ferromagnets. https://doi.org/10.1103/physrevlett.107.037202

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