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arXiv · 2110.04812

Magnetotransport in Fe3O4 nanoparticle arrays dominated by non-collinear surface spins

Seongjin Jang·Wenjie Kong·Hao Zeng
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Abstract

Magnetotransport in arrays of monodisperse magnetite nanoparticles has been studied as a function of annealing temperatures. Charge transport mechanisms change from thermally assisted interparticle tunneling to hopping between Fe-sites within the particle as the interparticle spacing is decreased. Despite this difference, magnetoresistance (MR) as a function of field shows a ubiquitous behavior dominated by non-collinear surface spins. All MR as a function of field can be fitted accurately by a Langevin-like function.

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Seongjin Jang, Wenjie Kong, Hao Zeng. 2021-10-10. Magnetotransport in Fe3O4 nanoparticle arrays dominated by non-collinear surface spins. https://doi.org/10.1103/physrevb.76.212403

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