Magneto-Ionics in Single-Layer Transition Metal Nitrides

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Magneto-ionics offers voltage-driven control of magnetism via ion transport (e.g., O, Li, H, F, N).
• Previous studies focused on cobalt nitrides, but iron nitrides present a new avenue for magneto-ionic applications.

Purpose of the Study:

• To demonstrate and evaluate magneto-ionic effects in single-layer iron nitride films at room temperature.
• To compare the performance of iron nitrides with cobalt nitrides in magneto-ionic applications.
• To investigate the underlying microstructural effects and theoretical underpinnings of nitrogen-ion motion in iron nitrides.

Main Methods:

• Experimental demonstration of magneto-ionic effects in iron nitride films.
• Performance evaluation at room temperature, including coercivity and saturation magnetization.
• Ab initio calculations to determine critical fields for nitrogen-ion motion based on atomic bonding strength.

Main Results:

• Iron nitrides exhibit magneto-ionic effects, though with higher activation energy and slower motion rates than cobalt nitrides.
• Ab initio calculations indicate a higher critical field for nitrogen-ion motion in iron nitrides (≈6.6 V nm⁻¹) compared to cobalt nitrides (≈5.3 V nm⁻¹).
• At large bias, iron nitride films demonstrate enhanced coercivity and saturation magnetization, outperforming cobalt nitrides in these aspects.

Conclusions:

• Iron nitrides present a viable material for magneto-ionic applications, offering distinct advantages in coercivity and saturation magnetization.
• The findings suggest potential integration of magneto-ionics within existing nitride semiconductor materials for advanced memory systems.
• Understanding microstructural effects is key to optimizing magneto-ionic performance in iron nitride systems.