Controlling Magneto‐Ionics by Defect Engineering Through Light Ion Implantation

AbstractMagneto‐ionics relies on the voltage‐driven transport of ions to modify magnetic properties. As a diffusion‐controlled mechanism, defects play a central role in determining ion motion and, hence, magneto‐ionic response. Here, the potential of ion implantation is exploited to engineer depth‐resolved defect type and density with the aim to control the magneto‐ionic behavior of Co3O4 thin films. It is demonstrated that through a single implantation process of light ions (He+) at 5 keV, the magneto‐ionic response of a nanostructured 50 nm thick Co3O4 film, in terms of rate and amount of induced magnetization, at short‐, mid‐, and long‐term voltage actuation, can be controlled by varying the generated collisional damage through the ion fluence. These results constitute a proof‐of‐principle that paves the way to further use ion implantation (tuning the ion nature, energy, fluence, target temperature, or using multiple implantations) to enhance performance in magneto‐ionic systems, with implications in ionic‐based devices.