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arXiv · 2001.08181

Boosting room temperature magneto-ionics in Co3O4

Julius de Rojas·Alberto Quintana·Aitor Lopeandía·Joaquín Salguero·José L. Costa-Krämer·Llibertat Abad·Maciej O. Liedke·Maik Butterling·Andreas Wagner·Lowie Henderick·Jolien Dendooven·Christophe Detavernier·Jordi Sort·Enric Menéndez
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Abstract

Voltage control of magnetism through electric field-induced oxygen motion (magneto-ionics) could represent a significant breakthrough in the pursuit for new strategies to enhance energy efficiency in a large variety of magnetic devices, such as magnetic micro-electro-mechanical systems (MEMS), magnetic logics, spin electronics, or neuromorphic computing, i.e., envisaging ultra-low power emulation of the biological synapse. Boosting the induced changes in magnetization, magneto-ionic motion and cyclability (endurance) continue to be key challenges to turn magneto-ionic phenomena into real applications. Here, we demonstrate that, without degrading cyclability, room temperature magneto-ionic motion in electrolyte-gated paramagnetic and fairly thick (> 100 nm) Co3O4 films largely depends on the configuration used to apply the electric field. In particular, magneto-ionic effects are significantly increased both in terms of generated magnetization (6 times larger: from 118.5 to 699.2 emu cm-3) and speed (35 times faster: from 33.1 to 1170.8 emu cm-3 h-1) if the electric field is applied across a conducting buffer layer (grown underneath the Co3O4 films), instead of directly contacting Co3O4. This is attributed to a greater uniformity and strength of the applied electric field when using the conducting layer. These results may trigger the use of oxygen magneto-ionics into promising new technologies, such as magnetic MEMS or brain-inspired computing, which require endurance and moderate speeds of operation.

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Julius de Rojas, Alberto Quintana, Aitor Lopeandía, Joaquín Salguero, José L. Costa-Krämer, Llibertat Abad, Maciej O. Liedke, Maik Butterling, Andreas Wagner, Lowie Henderick, Jolien Dendooven, Christophe Detavernier, Jordi Sort, Enric Menéndez. 2020-01-22. Boosting room temperature magneto-ionics in Co3O4. https://arxiv.org/abs/2001.08181

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