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arXiv · 2008.11391

Direct Imaging of Resonant Phonon-Magnon Coupling

Chenbo Zhao·Zhizhi Zhang·Yi Li·Wei Zhang·John E. Pearson·Ralu Divan·Jianbo Wang·Valentine Novosad·Qingfang Liu·Axel Hoffmann
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Abstract

Direct detection of phonons is important for the investigation of information interconversion between the resonantly coupled magnons and phonons. Here we report resonant coupling of magnons and phonons, which can be directly visualized by using micro focused Brillouin light scattering in Ni/LiNbO3 hybrid heterostructures. The patterns of surface acoustic wave phonons, originating from the interference between the original wave {\psi}0(A_0,k) and reflected wave {\psi}1(A_1,-k), can be modulated by magnetic field due to the magnon-phonon coupling. By analyzing the information of phonons obtained from Brillouin spectroscopy, the properties of the magnon system (Ni film), e.g., ferromagnetic resonance field and resonance linewidth can be determined. The results provide spatially resolved information about phonon manipulation and detection in a coupled magnon-phonon system.

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Chenbo Zhao, Zhizhi Zhang, Yi Li, Wei Zhang, John E. Pearson, Ralu Divan, Jianbo Wang, Valentine Novosad, Qingfang Liu, Axel Hoffmann. 2020-08-26. Direct Imaging of Resonant Phonon-Magnon Coupling. https://doi.org/10.1103/physrevapplied.15.014052

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