We report room-temperature long-distance spin transport of magnons in antiferromagnetic thin-film hematite doped with Zn. The additional dopants significantly alter the magnetic anisotropies, resulting in a complex equilibrium spin structure that is capable of efficiently transporting spin angular momentum at room temperature without the need for a well-defined, pure easy-axis or easy-plane anisotropy. We find intrinsic magnon spin-diffusion lengths of up to 1.5 μm, and magnetic domain governed decay lengths of 175 nm for the low-frequency magnons, through electrical transport measurements demonstrating that the introduction of nonmagnetic dopants does not strongly reduce the transport length scale, showing that the magnetic damping of hematite is not significantly increased. We observe a complex field dependence of the nonlocal signal independent of the magnetic state visible, in the local magnetoresistance and direct magnetic imaging of the antiferromagnetic domain structure. We explain our results in terms of a varying and applied field-dependent ellipticity of the magnon modes reaching the detector electrode allowing us to tune the spin transport.
|Original language||English (US)|
|Journal||Applied Physics Letters|
|State||Published - Dec 14 2020|
Bibliographical noteKAUST Repository Item: Exported on 2021-02-17
Acknowledged KAUST grant number(s): OSR-2019-CRG8-4048.2
Acknowledgements: All authors from Mainz also acknowledge support from MaHoJeRo (DAAD Spintronics network, Project Nos. 57334897 and 57524834), SPINþX (DFG SFB TRR 173, projects A01, A03, B02, and B12), DFG (No. 423441604), and KAUST (No. OSR-2019-CRG8-4048.2).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.