Design of Two-Dimensional Multiferroics with Direct Polarization-Magnetization Coupling

Area of Science:

• Condensed Matter Physics
• Materials Science
• Solid State Chemistry

Background:

• Two-dimensional (2D) ferromagnetism in van der Waals materials is a recent discovery.
• Electric field control of 2D magnetism is a key challenge in the field.

Purpose of the Study:

• To demonstrate magnetization reversal via polarization switching in a designed 2D multiferroic oxide.
• To explore intrinsic magnetoelectric coupling mechanisms for controlling 2D magnetism.

Main Methods:

• Utilized group theory analysis.
• Performed first-principles calculations.
• Investigated perovskite and double-perovskite bilayer structures.

Main Results:

• Induced ferroelectricity through specific octahedral rotations in a perovskite bilayer.
• Introduced simultaneous ferromagnetism in B-site ordered double-perovskite bilayers.
• Identified two coupling mechanisms enabling in-plane magnetization reversal by ferroelectric switching.

Conclusions:

• Provides guidelines for designing 2D multiferroics with intrinsic magnetoelectric coupling.
• Offers a pathway for electric field control of 2D magnetism.