Magnon-phonon coupling in wide band-gap magnetic rare-earth oxides
ORAL
Abstract
Rare earth atoms in wide band-gap oxides are ideal for collective excitations arising from the interplay between localized 4f magnetic moments and lattice vibrations. The magnon-phonon coupling arising from this interplay is central to next-generation magnonics. Here, from first principles, we investigate its microscopic origin by evaluating local magnetic moments and interactions including the Dzyaloshinskii–Moriya interaction along with phonon dynamics. The calculated phonon dispersion in CePO4 and CeVO4 shows mode-selective coupling between magnetic and lattice degrees of freedom1. In addition, the incorporation of Er3+ ions into the Ce4+ lattice of CeO2 shows measurable shifts in optical phonon frequencies along with renormalized magnon modes. This results in strong magnon-phonon coupling consistent with partially quenched Er–4f orbital moment.
1H. Paudyal, Y. Limbu, M. E. Flatté, and D. Paudyal, “Singly occupied 4f antiferromagnetic insulators: CePO4 and CeVO4,” Phys. Rev. B 112, 155112 (2025).
1H. Paudyal, Y. Limbu, M. E. Flatté, and D. Paudyal, “Singly occupied 4f antiferromagnetic insulators: CePO4 and CeVO4,” Phys. Rev. B 112, 155112 (2025).
*This work is supported by the U.S. Department of Energy. Calculations are performed on the Frontera supercomputer at the Texas Advanced Computing Center and the Argon high-performance computing system at the University of Iowa.
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Publication: H. Paudyal, Y. Limbu, M. E. Flatté, and D. Paudyal, "Singly occupied 4f antiferromagnetic insulators: CePO4 and CeVO4," Phys. Rev. B 112, 155112 (2025).
Presenters
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Hari Paudyal
- University of Iowa