Magneto-Ionic Control of Magnetic Properties

Magneto-ionics refers to the modulation of magnetic properties in materials by voltage-driven ion transport. In such systems, an applied electric field induces migration of mobile ions—commonly oxygen, nitrogen or hydrogen—within or across material interfaces. This ion displacement alters chemical bonding, oxidation states and lattice strain, which in turn influences magnetic ordering, anisotropy and coercivity. Magneto-ionics thus offers a route to switch between paramagnetic, ferromagnetic or antiferromagnetic states at room temperature without the need for external magnetic fields or large currents. Key advantages include ultralow energy consumption, non-volatility and potential for high device density. Recent progress has focused on enhancing ion mobility through defect engineering, exploring new ionic species and developing wireless or solid-state architectures. Together, these advances underpin emerging applications in memory, neuromorphic computing, spintronic sensors and reconfigurable magnonics. Fundamental studies continue to unravel redox-driven phase transformations, while practical demonstrations highlight reversible magnetisation control in thin films and heterostructures. Remaining challenges centre on controlling ion diffusion kinetics, minimising device fatigue and integrating magneto-ionic elements with established electronic platforms.

Research from Nature Portfolio

Recent studies have demonstrated wireless control of magnetism by immersing magnetic thin films in an electrolyte and inducing bipolar electrochemistry. This method achieves tunable transitions between paramagnetic and ferromagnetic states in cobalt nitride films without direct electrical contacts, providing a blueprint for bioelectronic and neuromorphic devices. In parallel, room-temperature reversible writing and deletion of magnetic skyrmions has been accomplished via hydrogen chemisorption and desorption on metallic surfaces. This approach exploits hydrogen-induced changes in magnetic anisotropy to nucleate or annihilate topologically protected spin textures, opening avenues for skyrmion-based information storage. Foundational work on voltage-driven nitrogen migration in cobalt nitride films established a new paradigm in which uniform, plane-wave-like ion fronts enable rapid, low-voltage and highly cyclable magnetisation switching, laying the groundwork for next-generation iontronic systems.

Magneto-Ionic Control of Magnetic Properties publication trend

The graph below shows the total number of articles in magneto-ionic control of magnetic properties across all publications each year (not limited to Nature Index journals).

Technical terms

Magneto-ionics: Voltage-driven transport of ions in magnetic materials to modulate magnetic properties. Exchange bias: A unidirectional shift of a magnetic hysteresis loop caused by coupling between ferromagnetic and antiferromagnetic layers. Skyrmion: A nanoscale, topologically protected spin vortex exhibiting particle-like stability in magnetic films. Bipolar electrochemistry: A wireless electrochemical process in which an object immersed in an electrolyte polarises under an external field, driving redox reactions at its extremities. Ionic gating: Use of an electric field and electrolyte to inject or extract ions in a material, altering its electronic or magnetic state.

References

1. Controlling Magneto‐Ionics by Defect Engineering Through Light Ion Implantation. Advanced Functional Materials (2024).
2. Wireless magneto-ionics: voltage control of magnetism by bipolar electrochemistry. Nature Communications (2023).
3. Reversible writing/deleting of magnetic skyrmions through hydrogen adsorption/desorption. Nature Communications (2022).
4. Voltage-driven motion of nitrogen ions: a new paradigm for magneto-ionics. Nature Communications (2020).
5. Solid-State Lithium Ion Supercapacitor for Voltage Control of Skyrmions. Nano Letters (2023).
6. Nitrogen-Based Magneto-ionic Manipulation of Exchange Bias in CoFe/MnN Heterostructures. ACS Nano (2023).
7. Advances in magneto-ionic materials and perspectives for their application. APL Materials (2021).