PT-Symmetric Antiferromagnets as Building Blocks for Anomalous Transport

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Antiferromagnets with space-time inversion (PT) symmetry typically suppress the anomalous Hall effect (AHE).
• This suppression limits the application of these materials in spintronics.
• A need exists for strategies to engineer AHE in PT-symmetric antiferromagnets.

Purpose of the Study:

• To propose a symmetry-guided design strategy for inducing AHE in PT-symmetric antiferromagnets.
• To identify criteria for selecting magnetic materials suitable for this strategy.
• To demonstrate the feasibility of creating AHE in stacked antiferromagnetic bilayers.

Main Methods:

• Developing screening criteria based on magnetic layer groups and interlayer mirror symmetry.
• Utilizing a tight-binding model to simulate the electronic and magnetic properties of stacked structures.
• Performing first-principles calculations on bilayer MnPSe3 to validate the design framework.

Main Results:

• Identified stacked bilayers of PT-symmetric antiferromagnets can exhibit AHE.
• Demonstrated that these bilayers are magnetically compensated and belong to a distinct type IV class of magnets.
• Confirmed the realization of a symmetry-enforced layer-constructive Hall effect in bilayer MnPSe3.

Conclusions:

• Symmetry-controlled stacking is a viable approach for engineering unconventional magnetic materials.
• This strategy enables the induction of AHE in materials where it is typically suppressed.
• The findings open new avenues for spintronic applications utilizing antiferromagnets.