Pure spin current polarizer enabled by antiferromagnetic insulator.

Area of Science:

• Spintronics
• Condensed Matter Physics
• Materials Science

Background:

• Pure spin current facilitates spin information transport without charge flow, crucial for advanced information technologies.
• A controllable pure spin current polarizer is essential for spintronics but has remained elusive.
• Existing methods lack efficient control over both transmittance and spin polarization.

Purpose of the Study:

• To demonstrate a highly efficient pure spin current polarizer at room temperature.
• To enable control over spin polarization and transmittance for spintronic applications.
• To explore novel routes for energy-efficient spintronic devices.

Main Methods:

• Utilized a single-domain antiferromagnetic insulator film.
• Employed structural engineering and spin-lattice coupling for device fabrication.
• Investigated magnon current properties, including transmittance and spin polarization.

Main Results:

• Achieved a highly efficient pure spin current polarizer operating at room temperature.
• Demonstrated large differential magnon current transmittance.
• Confirmed that transmitted magnon current spin polarization aligns with the Néel vector of the polarizer.
• Showcased large modulation of damping-like torque and generation of out-of-plane-polarized magnon current.

Conclusions:

• The developed device functions as an efficient pure spin current polarizer at room temperature.
• The alignment of spin polarization with the Néel vector offers new possibilities for spintronic device design.
• This polarizer is a key building block for future spintronics based on pure spin current and energy-efficient devices.