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arXiv · 2309.13721

Tuning the Néel temperature in an antiferromagnet: the case of NixCo1-xO microstructures

Anna Mandziak·Guiomar D. Soria·José Emilio Prieto·Pilar Prieto·Cecilia Granados-Miralles·Adrian Quesada·Michael Foerster·Lucia Aballe·Juan de la Figuera
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Abstract

We show that it is possible to tune the Néel temperature of nickel(II)-cobalt(II) oxide films by changing the Ni to Co ratio. We grow single crystalline micrometric triangular islands with tens of nanometers thickness on a Ru(0001) substrate using high temperature oxygen-assisted molecular beam epitaxy. Composition is controlled by adjusting the deposition rates of Co and Ni. The morphology, shape, crystal structure and composition are determined by low-energy electron microscopy and diffraction, and synchrotron-based x-ray absorption spectromicroscopy. The antiferromagnetic order is observed by x-ray magnetic linear dichroism. Antiferromagnetic domains up to micrometer width are observed.

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Anna Mandziak, Guiomar D. Soria, José Emilio Prieto, Pilar Prieto, Cecilia Granados-Miralles, Adrian Quesada, Michael Foerster, Lucia Aballe, Juan de la Figuera. 2023-09-24. Tuning the Néel temperature in an antiferromagnet: the case of NixCo1-xO microstructures. https://doi.org/10.1038/s41598-019-49642-8

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