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arXiv · 2005.12113

Nonlinear losses in magnon transport due to four-magnon scattering

Tobias Hula·Katrin Schultheiss·Aleksandr Buzdakov·Lukas Körber·Mauricio Bejarano·Luis Flacke·Lukas Liensberger·Mathias Weiler·Justin M. Shaw·Hans T. Nembach·Jürgen Fassbender·Helmut Schultheiss
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Abstract

We report on the impact of nonlinear four-magnon scattering on magnon transport in microstructured Co25Fe75 waveguides with low magnetic damping. We determine the magnon propagation length with microfocused Brillouin light scattering over a broad range of excitation powers and detect a decrease of the attenuation length at high powers. This is consistent with the onset of nonlinear four-magnon scattering. Hence, it is critical to stay in the linear regime, when deriving damping parameters from the magnon propagation length. Otherwise, the intrinsic nonlinearity of magnetization dynamics may lead to a misinterpretation of magnon propagation lengths and, thus, to incorrect values of the magnetic damping of the system.

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Tobias Hula, Katrin Schultheiss, Aleksandr Buzdakov, Lukas Körber, Mauricio Bejarano, Luis Flacke, Lukas Liensberger, Mathias Weiler, Justin M. Shaw, Hans T. Nembach, Jürgen Fassbender, Helmut Schultheiss. 2020-05-25. Nonlinear losses in magnon transport due to four-magnon scattering. https://doi.org/10.1063/5.0015269

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