Nitrogen magneto-ionics
Abstract
So far, magneto-ionics, understood as voltage-driven ion transport in magnetic materials, has largely relied on controlled migration of oxygen ion/vacancy and, to a lesser extent, lithium and hydrogen. Here, we demonstrate efficient, room-temperature, voltage-driven nitrogen transport (i.e., nitrogen magneto-ionics) by electrolyte-gating of a single CoN film (without an ion-reservoir layer). Nitrogen magneto-ionics in CoN is compared to oxygen magneto-ionics in Co3O4, both layers showing a nanocrystalline face-centered-cubic structure and reversible voltage-driven ON-OFF ferromagnetism. In contrast to oxygen, nitrogen transport occurs uniformly creating a plane-wave-like migration front, without assistance of diffusion channels. Nitrogen magneto-ionics requires lower threshold voltages and exhibits enhanced rates and cyclability. This is due to the lower activation energy for ion diffusion and the lower electronegativity of nitrogen compared to oxygen. These results are appealing for the use of magneto-ionics in nitride semiconductor devices, in applications requiring endurance and moderate speeds of operation, such as brain-inspired computing.
Cite
@article{arxiv.2003.11137,
title = {Nitrogen magneto-ionics},
author = {Julius de Rojas and Alberto Quintana and Aitor Lopeandía and Joaquín Salguero and Beatriz Muñiz and Fatima Ibrahim and Mairbek Chshiev and Maciej O. Liedke and Maik Butterling and Andreas Wagner and Veronica Sireus and Llibertat Abad and Christopher J. Jensen and Kai Liu and Josep Nogués and José L. Costa-Krämer and Enric Menéndez and Jordi Sort},
journal= {arXiv preprint arXiv:2003.11137},
year = {2020}
}
Comments
35 pages, 5 main figures, 1 Table, supplementary information included