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arXiv · 1909.06152

Tunable perpendicular exchange bias in oxide heterostructures

Gideok Kim·Yury Khaydukov·Martin Bluschke·Y. Eren Suyolcu·Georg Christiani·Kwanghyo Son·Christopher Dietl·Thomas Keller·Eugen Weschke·P. A. van Aken·Gennady Logvenov·Bernhard Keimer
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Abstract

The exchange bias effect is an essential component of magnetic memory and spintronic devices. Whereas recent research has shown that anisotropies perpendicular to the device plane provide superior stability against thermal noise, it has proven remarkably difficult to realize perpendicular exchange bias in thin-film structures. Here we demonstrate a strong perpendicular exchange bias effect in heterostructures of the quasi-two-dimensional canted antiferromagnet La$_2$CuO$_4$ and ferromagnetic (La,Sr)MnO$_3$ synthesized by ozone-assisted molecular beam epitaxy. The magnitude of this effect can be controlled via the doping level of the cuprate layers. Canted antiferromagnetism of layered oxides is thus a new and potentially powerful source of uniaxial anisotropy in magnetic devices.

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Gideok Kim, Yury Khaydukov, Martin Bluschke, Y. Eren Suyolcu, Georg Christiani, Kwanghyo Son, Christopher Dietl, Thomas Keller, Eugen Weschke, P. A. van Aken, Gennady Logvenov, Bernhard Keimer. 2019-09-13. Tunable perpendicular exchange bias in oxide heterostructures. https://doi.org/10.1103/physrevmaterials.3.084420

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