Interlayer coupling of valley and layer in the homostructure bilayer ScI₂

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Valleytronics in 2D materials often relies on complex heterostructures.
• Understanding valley-layer coupling in homostructures is crucial for device simplification.

Purpose of the Study:

• To investigate valley-layer coupling mechanisms in 2D homostructures.
• To explore ferroelectric and ferrovalley properties in bilayer ScI2.

Main Methods:

• Computational modeling and theoretical analysis of bilayer ScI2.
• Investigating the effects of interlayer sliding on electronic and polarization properties.

Main Results:

• Bilayer ScI2 exhibits coupled ferroelectric and ferrovalley characteristics.
• Interlayer sliding tunes valley polarization (114 meV) and ferroelectric polarization (3 × 10^-11 C m^-1).
• High Curie temperature (615 K) enables room-temperature applications.

Conclusions:

• Bilayer ScI2 presents a promising homostructure for valleytronics.
• Sliding symmetry offers a novel mechanism for valley polarization control.
• The material shows potential for switchable anomalous Hall effect devices.