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arXiv · 1907.13393

Large spin Hall magnetoresistance in antiferromagnetic α-Fe2O3/Pt heterostructures

Johanna Fischer·Matthias Althammer·Nynke Vlietstra·Hans Huebl·Sebastian T. B. Goennenwein·Rudolf Gross·Stephan Geprägs·Matthias Opel
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Abstract

We investigate the spin Hall magnetoresistance (SMR) at room temperature in thin film heterostructures of antiferromagnetic, insulating, (0001)-oriented alpha-Fe2O3 (hematite) and Pt. We measure their longitudinal and transverse resistivities while rotating an applied magnetic field of up to 17T in three orthogonal planes. For out-of-plane magnetotransport measurements, we find indications for a multidomain antiferromagnetic configuration whenever the field is aligned along the film normal. For in-plane field rotations, we clearly observe a sinusoidal resistivity oscillation characteristic for the SMR due to a coherent rotation of the Neel vector. The maximum SMR amplitude of 0.25% is, surprisingly, twice as high as for prototypical ferrimagnetic Y3Fe5O12/Pt heterostructures. The SMR effect saturates at much smaller magnetic fields than in comparable antiferromagnets, making the alpha-Fe2O3/Pt system particularly interesting for room-temperature antiferromagnetic spintronic applications.

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Johanna Fischer, Matthias Althammer, Nynke Vlietstra, Hans Huebl, Sebastian T. B. Goennenwein, Rudolf Gross, Stephan Geprägs, Matthias Opel. 2020-01-18. Large spin Hall magnetoresistance in antiferromagnetic α-Fe2O3/Pt heterostructures. https://doi.org/10.1103/physrevapplied.13.014019

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