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arXiv · 2604.23943

Nearly Isotropic Magnon Transport in Epitaxial Lithium Aluminum Ferrite Thin Films

Yiming Li·Katya Mikhailova·Lerato Takana·Daisy O'Mahoney·Sauviz P. Alaei·Guanxiong Qu·Dominic Petruzzi·Samuel Crossley·Harold Y. Hwang·Ian R. Fisher·Clare C. Yu·Yuri Suzuki
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Abstract

Low-loss magnetic insulating thin films are promising for information transport via magnons, where isotropic in-plane magnon propagation is desirable. We report nonlocal measurements of electrically and thermally generated magnons in epitaxial (001) lithium aluminum ferrite Li$_{0.5}$Al$_{0.7}$Fe$_{1.8}$O$_4$ thin films with pronounced fourfold in-plane magnetic anisotropy. By measuring the inverse spin Hall signal as a function of the magnon diffusion distance, we deduce magnon diffusion lengths that are nearly identical along the [100] and [110] directions at 250~K. This isotropy is consistent with a nearly isotropic exchange stiffness. These results highlight spinel ferrites as viable platforms for isotropic magnon transport.

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Yiming Li, Katya Mikhailova, Lerato Takana, Daisy O'Mahoney, Sauviz P. Alaei, Guanxiong Qu, Dominic Petruzzi, Samuel Crossley, Harold Y. Hwang, Ian R. Fisher, Clare C. Yu, Yuri Suzuki. 2026-04-27. Nearly Isotropic Magnon Transport in Epitaxial Lithium Aluminum Ferrite Thin Films. https://arxiv.org/abs/2604.23943

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