Skip to main content

Anisotropic Magnon Spin Transport in Ultrathin Spinel Ferrite Thin Films─Evidence for Anisotropy in Exchange Stiffness

Cornell Affiliated Author(s)

Author

Ruofan Li
Peng Li
Di Yi
Lauren Riddiford
Yahong Chai
Yuri Suzuki
Daniel Ralph
Tianxiang Nan

Abstract

Magnon-mediated spin flow in magnetically ordered insulators enables long-distance spin-based information transport with low dissipation. In the materials studied to date, no anisotropy has been observed in the magnon propagation length as a function of propagation direction. Here, we report measurements of magnon spin transport in a spinel ferrite, magnesium aluminum ferrite MgAl0.5Fe1.5O4 (MAFO), which has a substantial in-plane 4-fold magnetic anisotropy. We observe spin diffusion lengths > 0.8 μm at room temperature in 6 nm films, with spin diffusion lengths 30% longer along the easy axes compared to the hard axes. The sign of this difference is opposite to the effects just of anisotropy in the magnetic energy for a uniform magnetic state. We suggest instead that accounting for anisotropy in exchange stiffness is necessary to explain these results. These findings provide an approach for controlling magnon transport via strain, which opens new opportunities for designing magnonic devices. © 2022 American Chemical Society.

Date Published

Journal

American Chemical Society (ACS)

Volume

22

Issue

3

Number of Pages

1167-1173,

URL

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85124143891&doi=10.1021%2facs.nanolett.1c04332&partnerID=40&md5=5ad7ea52502d5e7f93a590fe19278404

DOI

10.1021/acs.nanolett.1c04332

Funding Source

NNCI-2025 233
N00014-15-1-0045
FA 9550-20-1-0293
DMR-1719 875
52 073 158,52 161 135 103

Download citation