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arXiv · 1904.11321

High Spin-Wave Propagation Length Consistent with Low Damping in a Metallic Ferromagnet

Luis Flacke·Lukas Liensberger·Matthias Althammer·Hans Huebl·Stephan Geprägs·Katrin Schultheiss·Aleksandr Buzdakov·Tobias Hula·Helmut Schultheiss·Eric R. J. Edwards·Hans T. Nembach·Justin M. Shaw·Rudolf Gross·Mathias Weiler
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Abstract

We report ultra-low intrinsic magnetic damping in Co$_{\text{25}}$Fe$_{\text{75}}$ heterostructures, reaching the low $10^{-4}$ regime at room temperature. By using a broadband ferromagnetic resonance technique, we extracted the dynamic magnetic properties of several Co$_{\text{25}}$Fe$_{\text{75}}$-based heterostructures with varying ferromagnetic layer thickness. By estimating the eddy current contribution to damping, measuring radiative damping and spin pumping effects, we found the intrinsic damping of a 26\,nm thick sample to be $$\alpha_{\mathrm{0}} \lesssim 3.18\times10^{-4}$. Furthermore, using Brillouin light scattering microscopy we measured spin-wave propagation lengths of up to $(21\pm1)\,\mathrm{\mu m}$ in a 26 nm thick Co$_{\text{25}}$Fe$_{\text{75}}$ heterostructure at room temperature, which is in excellent agreement with the measured damping.

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Luis Flacke, Lukas Liensberger, Matthias Althammer, Hans Huebl, Stephan Geprägs, Katrin Schultheiss, Aleksandr Buzdakov, Tobias Hula, Helmut Schultheiss, Eric R. J. Edwards, Hans T. Nembach, Justin M. Shaw, Rudolf Gross, Mathias Weiler. 2019-04-25. High Spin-Wave Propagation Length Consistent with Low Damping in a Metallic Ferromagnet. https://doi.org/10.1063/1.5102132

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