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arXiv · 1809.11059

Interface-induced anomalous Nernst effect in Fe3O4/Pt-based heterostructures

R. Ramos·T. Kikkawa·A. Anadón·I. Lucas·T. Niizeki·K. Uchida·P. A. Algarabel·L. Morellón·M. H. Aguirre·M. R. Ibarra·E. Saitoh
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Abstract

We have studied the anomalous Nernst effect (ANE) in [Fe3O4/Pt]-based heterostructures, by measuring the ANE-induced electric field with a magnetic field applied normal to the sample surface, in the perpendicular magnetized configuration, where only the ANE is expected. An ANE voltage is observed for [Fe3O4/Pt]n multilayers, and we further investigated its origin by performing measurements in [Fe3O4/Pt/Fe3O4] trilayers as a function of the Pt thickness. Our results suggest the presence of an interface-induced ANE. Despite of this ANE, the spin Seebeck effect is the dominant mechanism for the transverse thermoelectric voltage in the in-plane magnetized configuration, accounting for about 70 % of the measured voltage in the multilayers.

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R. Ramos, T. Kikkawa, A. Anadón, I. Lucas, T. Niizeki, K. Uchida, P. A. Algarabel, L. Morellón, M. H. Aguirre, M. R. Ibarra, E. Saitoh. 2018-09-28. Interface-induced anomalous Nernst effect in Fe3O4/Pt-based heterostructures. https://doi.org/10.1063/1.5063553

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