Deterministic optical control of room temperature multiferroicity in BiFeO₃ thin films

Area of Science:

• Materials Science
• Condensed Matter Physics
• Optoelectronics

Background:

• Controlling ferroic orders (ferroelectricity, ferromagnetism, ferroelasticity) optically is challenging due to energy scale mismatches.
• Bismuth ferrite (BiFeO3) is a material exhibiting multiple ferroic orders, making it a candidate for multiferroic applications.

Purpose of the Study:

• To demonstrate optical manipulation of multiple ferroic orders in epitaxial mixed-phase BiFeO3 thin films.
• To investigate the underlying mechanism of light-driven ferroic order control.
• To achieve deterministic laser writing and erasure of ferroic domain patterns.

Main Methods:

• Utilized laser illumination to control ferroic orders in BiFeO3 thin films at ambient temperature.
• Employed phase-field simulations to understand the light-driven flexoelectric effect.
• Performed sequential laser writing and erasure experiments to demonstrate control.

Main Results:

• Achieved targeted formation of ordered domains via a light-driven flexoelectric effect.
• Demonstrated precise sequential laser writing and erasure of different domain patterns.
• Showcased deterministic optical control of multiferroicity at room temperature.

Conclusions:

• Optical methods can effectively control multiple ferroic orders in BiFeO3 thin films.
• The light-driven flexoelectric effect is a key mechanism for this control.
• The findings suggest potential advancements for optoelectronics and related applications.