Large Photoinduced Tuning of Ferroelectricity in Sliding Ferroelectrics

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Harvesting ferroelectricity in 2D materials is achieved by stacking nonpolar monolayers.
• Interlayer charge transfer in specific stacking sequences generates out-of-plane dipoles, tunable via interlayer sliding.

Purpose of the Study:

• To demonstrate robust tuning of electric polarization in rhombohedrally-stacked bilayer MoS2 using photoexcitation.
• To elucidate the mechanisms and roles of photoexcitation in modulating sliding ferroelectricity.

Main Methods:

• Ab initio calculations were employed to study rhombohedrally-stacked bilayer MoS2.
• Investigated the effects of photoexcitation on polarization under varying light intensities.

Main Results:

• Photoexcitation robustly tunes out-of-plane electric polarization over a large range for a given sliding.
• Tuning originates from photoinduced structural distortion and photoexcited carrier distribution.
• Different light intensities play distinct roles in modulating sliding ferroelectricity.

Conclusions:

• Photoexcitation offers a powerful method for manipulating polarization in 2D van der Waals materials.
• Understanding light-matter interactions is key to controlling ferroelectric properties in advanced materials.