Strong In-Plane Magnetization and Spin Polarization in (Co_0.15Fe_0.85)₅GeTe₂/Graphene van der Waals Heterostructure...

Area of Science:

• Materials Science
• Condensed Matter Physics
• Spintronics

Background:

• Van der Waals (vdW) magnets offer tunable magnetic properties but often require cryogenic temperatures for spintronic applications.
• Existing vdW magnet spintronic devices typically exhibit out-of-plane or canted magnetization, limiting their practical use.

Purpose of the Study:

• To develop room-temperature spintronic devices using vdW magnets.
• To investigate the in-plane magnetization and spin polarization of (Co_0.15Fe_0.85)₅GeTe₂ (CFGT) in heterostructures with graphene.

Main Methods:

• Density Functional Theory (DFT) calculations to determine anisotropy origins.
• Magnetization measurements to confirm ferromagnetism and remanence.
• Fabrication and characterization of CFGT/graphene heterostructures for spin injection and detection.

Main Results:

• CFGT exhibits ferromagnetism above room temperature with clear remanence.
• DFT calculations indicate Co substitution in Fe layers influences anisotropy.
• Experimental results demonstrate efficient spin injection/detection and strong in-plane magnetization with negative spin polarization at the CFGT/graphene interface.

Conclusions:

• CFGT's room-temperature in-plane magnetization is suitable for graphene lateral spin-valve devices.
• This work highlights CFGT's potential for advanced spintronic technologies.
• The study paves the way for practical, high-temperature spintronic applications.