# Electric Field Modulation of Interlayer Coupling via Piezostrain in a Synthetic Antiferromagnet

## TL;DR

This paper shows how an electric field can control magnetic coupling in a synthetic antiferromagnet, offering a way to build energy-efficient spintronic devices.

## Contribution

The study demonstrates electric field modulation of interlayer coupling via piezoelectric strain in a Co/Ru/Co SAF on PMN-PT.

## Key findings

- Electric field-induced strain modulates both IEC and uniaxial magnetic anisotropy energy in the Co/Ru/Co/PMN-PT structure.
- In-plane piezoelectric strain enhances antiferromagnetic IEC strength in the SAF layer.
- Modulation efficiency is strongly correlated with the thickness of the Ru spacer layer.

## Abstract

Controlling the interlayer exchange coupling (IEC) in synthetic antiferromagnets (SAFs) using an electric field is a promising approach for developing energy‐efficient spintronic devices, as it enables magnetization switching without electrical current. In this study, the modulation of the IEC through electric field‐induced strain in a Co/Ru/Co SAF on a Pb(Mg1/3Nb2/3)O3‐PbTiO3 (PMN‐PT) multiferroic heterostructure is demonstrated. It is found that both the IEC and the uniaxial magnetic anisotropy energy are modulated by applying an electric field to the Co/Ru/Co/PMN‐PT structure. This modulation is evident from the behavior of the minor hysteresis loops observed in our experiments and micromagnetic simulations. Additionally, it is clarified that the in‐plane piezoelectric strain transferred from the PMN‐PT to the Co/Ru/Co SAF layer enhances the strength of the antiferromagnetic IEC. Notably, the efficiency of this enhancement due to piezoelectric strain is strongly correlated with the thickness of the Ru spacer, a finding that aligns with our first‐principles calculations. Controlling the IEC via the piezoelectric strain transfer effect using an electric field enables the manipulation of antiferromagnetic order with extremely low energy consumption, offering significant potential for energy‐efficient spintronic memory devices.

Controlling the interlayer exchange coupling (IEC) in synthetic antiferromagnets (SAFs) using an electric field is a promising route toward energy‐efficient spintronic devices. In this study, electric field induced‐strain modulation of IEC in Co/Ru/Co SAF/PMN‐PT is demonstrated. The modulation efficiency depends on the initial IEC strength; stronger IECs lead to higher modulation efficiencies.