Tip Interface Exchange-Coupling Based on "Bi-Anisotropic" Nanocomposites with Low Rare-Earth Content

Area of Science:

• Materials Science
• Nanotechnology
• Magnetism

Background:

• Samarium Cobalt (SmCo5) and Cobalt (Co) are key magnetic materials.
• Developing high-performance magnetic nanocomposites with reduced rare-earth content is a significant challenge.

Purpose of the Study:

• To fabricate and characterize novel SmCo5/Co magnetic nanocomposites.
• To investigate the magnetic performance and exchange-coupling mechanisms in these bi-anisotropic materials.
• To achieve high coercivity and remanence with a low rare-earth content.

Main Methods:

• Bottom-up fabrication process involving solution-phase synthesis and chemical deposition.
• Preparation of anisotropic SmCo5 nanochips and Co nanorods.
• Simultaneous alignment of nanochips and nanorods under an external magnetic field.
• Magnetic measurements and 3-D micromagnetic simulations.

Main Results:

• Successfully fabricated SmCo5/Co magnetic nanocomposites with varying Co content (10-80 wt%).
• Achieved high magnetic performance, including coercivity near 10 kOe and 31% increased remanence compared to single-phase SmCo5.
• Demonstrated the first applicable exchange-coupled nanocomposites with rare-earth content below 7 wt% developed via this method.
• Micromagnetic simulations revealed a shift in the Co phase reversal mechanism due to interface exchange-coupling.

Conclusions:

• The developed bottom-up approach enables the creation of high-performance SmCo5/Co magnetic nanocomposites.
• These nanocomposites offer superior magnetic properties with significantly reduced rare-earth content.
• Interface exchange-coupling plays a crucial role in enhancing magnetic reversal mechanisms.