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Electric-Field-Controlled Interconversion of Antiferromagnetic States in a Two-Dimensional Antiferroelectric Halide
Wan Zhao1,2, Xiaodong Zhou1,2, Tao Zhu1,2
1Institute of Quantum Materials and Devices, School of Electronic and Information Engineering, Tiangong University, Tianjin, China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|August 14, 2026
Summary
We demonstrate electric-field control of antiferromagnetic electronic states using a novel perovskite material. This allows switching between spin-split altermagnetic and spin-degenerate states for low-power spintronics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Electric-field control of spin properties in antiferromagnets is crucial for developing low-power spintronic devices but remains underexplored.
- Achieving reversible switching between distinct antiferromagnetic (AFM) electronic states via electric fields is a significant challenge.
Purpose of the Study:
- To propose and verify a method for electric-field-driven switching between symmetry-distinct altermagnetic (AM) and type-IV AFM states.
- To identify a suitable material platform for realizing this electric-field-induced phase transition and its associated electronic structure changes.
- To enable reversible interconversion between spin-split and spin-degenerate electronic structures for spintronic applications.
Main Methods:
- Utilizing first-principles calculations to investigate the electronic and magnetic properties of candidate materials.
- Identifying organic-inorganic halide perovskite multiferroic monolayers as potential platforms.
- Simulating the effect of in-plane electric fields on the antiferroelectric (AFE) structures and their corresponding AFM electronic states.
Main Results:
- The monolayer was identified as a promising candidate material.
- Two inequivalent AFE structures were found, hosting distinct AFM electronic states: one AM with spin splitting, the other type-IV AFM with spin-degenerate bands.
- A low in-plane electric field (0.017 V/Å) was shown to drive the transition between these AFE phases, switching the electronic states.
- Distinct Kerr rotation responses for the AM and type-IV AFM states enable optical detection of the electric-field-driven switching.
Conclusions:
- Antiferroelectric interconversion provides a novel route for electrically programming symmetry-distinct AFM electronic states.
- This ferroic-order-based approach offers a new pathway for developing low-power, optically readable antiferromagnetic spintronics.
- The proposed mechanism in the monolayer demonstrates the potential for practical spintronic device applications.
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