Sliding Ferroelectric Control of Unconventional Magnetism in Stacked Bilayers

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Unconventional magnetism, exhibiting ferromagnetism-like properties with compensated magnetization, is crucial for advancing antiferromagnetic spintronics.
• Controlling these magnetic states is key for next-generation electronic devices.

Purpose of the Study:

• To establish a general symmetry-based stacking rule for controlling unconventional magnetism in bilayer systems.
• To enable simultaneous switching of electric polarization and spin-related phenomena via sliding ferroelectricity.

Main Methods:

• Symmetry analysis of 80 layer groups to derive a general stacking rule.
• Development of a connection operator to link stacked bilayers.
• First-principles calculations to validate the proposed mechanism.

Main Results:

• Identified stacking orders allowing simultaneous switching of electric polarization and spin splitting/anomalous Hall effect in altermagnets.
• Extended the stacking rule to collinear compensated ferrimagnets.
• Demonstrated ferroelectric control of spin polarization and anomalous Hall effect in AgF2 and Fe2MoSe4 bilayers.

Conclusions:

• A general symmetry strategy for ferroelectric control of unconventional magnetism in bilayers has been provided.
• This work opens new avenues for exploring novel magnetoelectric coupling phenomena.