Tan Zhengwei, Martins Sofia, Escobar Michael, de Rojas Julius, Ibrahim Fatima, Chshiev Mairbek, Quintana Alberto, Lopeandia Aitor, Costa-Krämer José L, Menéndez Enric, Sort Jordi
Departament de Física, Universitat Autònoma de Barcelona, E-08193 Cerdanyola del Vallès, Spain.
Department of Physics, Durham University, South Road, DH1 3LE Durham, U.K.
ACS Appl Mater Interfaces. 2022 Oct 5;14(39):44581-44590. doi: 10.1021/acsami.2c12847. Epub 2022 Sep 21.
Magneto-ionics is an emerging actuation mechanism to control the magnetic properties of materials voltage-driven ion motion. This effect largely relies on the strength and penetration of the induced electric field into the target material, the amount of generated ion transport pathways, and the ionic mobility inside the magnetic media. Optimizing all these factors in a simple way is a huge challenge, although highly desirable for technological applications. Here, we demonstrate that the introduction of suitable transition-metal elements to binary nitride compounds can drastically boost magneto-ionics. More specifically, we show that the attained magneto-ionic effects in CoN films (, saturation magnetization, toggling speeds, and cyclability) can be drastically enhanced through 10% substitution of Co by Mn in the thin-film composition. Incorporation of Mn leads to transformation from nanocrystalline into amorphous-like structures, as well as from metallic to semiconducting behaviors, resulting in an increase of N-ion transport channels. calculations reveal a lower energy barrier for CoMn-N compared to Co-N that provides a fundamental understanding of the crucial role of Mn addition in the voltage-driven magnetic effects. These results constitute an important step forward toward enhanced voltage control of magnetism electric field-driven ion motion.
磁离子学是一种新兴的驱动机制，通过电压驱动离子运动来控制材料的磁性。这种效应在很大程度上依赖于感应电场进入目标材料的强度和穿透深度、产生的离子传输路径的数量以及磁性介质内部的离子迁移率。以简单的方式优化所有这些因素是一项巨大的挑战，尽管这对于技术应用来说非常理想。在这里，我们证明向二元氮化物化合物中引入合适的过渡金属元素可以极大地增强磁离子学效应。更具体地说，我们表明，通过在薄膜成分中用10%的锰替代钴，可以大幅增强CoN薄膜中的磁离子效应（饱和磁化强度、切换速度和循环性）。锰的掺入导致从纳米晶结构转变为类非晶结构，以及从金属行为转变为半导体行为，从而增加了氮离子传输通道。计算结果表明，与Co-N相比，CoMn-N的能垒更低，这为理解锰的添加在电压驱动磁效应中的关键作用提供了基本依据。这些结果是朝着增强磁场的电压控制（通过电场驱动离子运动）迈出的重要一步。
