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arXiv · 1701.02041

Nonlocal magnon spin transport in NiFe$_2$O$_4$ thin films

J. Shan·P. Bougiatioti·L. Liang·G. Reiss·T. Kuschel·B. J. van Wees
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Abstract

We report magnon spin transport in nickel ferrite (NiFe$_2$O$_4$, NFO)/ platinum (Pt) bilayer systems at room temperature. A nonlocal geometry is employed, where the magnons are excited by the spin Hall effect or by the Joule heating induced spin Seebeck effect at the Pt injector, and detected at a certain distance away by the inverse spin Hall effect at the Pt detector. The dependence of the nonlocal magnon spin signals as a function of the magnetic field is closely related to the NFO magnetization behavior. In contrast, we observe that the magnetoresistance measured locally at the Pt injector does not show a clear relation with the average NFO magnetization. We estimate the magnon spin relaxation length to be 3.1 $\pm$ 0.2 $\mu$m in the investigated NFO samples.

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J. Shan, P. Bougiatioti, L. Liang, G. Reiss, T. Kuschel, B. J. van Wees. 2017-01-08. Nonlocal magnon spin transport in NiFe$_2$O$_4$ thin films. https://doi.org/10.1063/1.4979408

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