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arXiv · 2311.16688

Coherent phonon-magnon interactions detected by micro-focused Brillouin light scattering spectroscopy

Yannik Kunz·Matthias Küß·Michael Schneider·Moritz Geilen·Philipp Pirro·Manfred Albrecht·Mathias Weiler
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Abstract

We investigated the interaction of surface acoustic waves and spin waves with spatial resolution by micro-focused Brillouin light scattering spectroscopy in a Co$_{40}$Fe$_{40}$B$_{20}$ ferromagnetic layer on a LiNbO$_{3}$-piezoelectric substrate. We experimentally demonstrate that the magnetoelastic excitation of magnons by phonons is coherent by studying the interfering BLS-signals of the phonons and magnons during their conversion process.We find a pronounced spatial dependence of the phonon annihilation and magnon excitation which we map as a function of the magnetic field. The coupling efficiency of the surface acoustic waves (SAWs) and the spin waves (SWs) is characterized by a magnetic field dependent decay of the SAWs amplitude.

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Yannik Kunz, Matthias Küß, Michael Schneider, Moritz Geilen, Philipp Pirro, Manfred Albrecht, Mathias Weiler. 2023-11-28. Coherent phonon-magnon interactions detected by micro-focused Brillouin light scattering spectroscopy. https://arxiv.org/abs/2311.16688

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