Strain-controlled nonvolatile magnetization switching

TL;DR

This paper explores strain-induced nonvolatile magnetization switching in ferromagnetic/piezoelectric hybrids at room temperature, demonstrating potential for electrically controlled magnetic memory devices.

Contribution

It introduces a model and engineering strategies to achieve efficient, nonvolatile magnetization switching via elastic strain in ferromagnetic thin films.

Findings

Significant strain-induced magnetization change observed

Inefficient strain transfer and domain formation limit effects

Model suggests engineered hybrids can enable nonvolatile switching

Abstract

We investigate different approaches towards a nonvolatile switching of the remanent magnetization in single-crystalline ferromagnets at room temperature via elastic strain using ferromagnetic thin film/piezoelectric actuator hybrids. The piezoelectric actuator induces a voltage-controllable strain along different crystalline directions of the ferromagnetic thin film, resulting in modifications of its magnetization by converse magnetoelastic effects. We quantify the magnetization changes in the hybrids via ferromagnetic resonance spectroscopy and superconducting quantum interference device magnetometry. These measurements demonstrate a significant strain-induced change of the magnetization, limited by an inefficient strain transfer and domain formation in the particular system studied. To overcome these obstacles, we address practicable engineering concepts and use a model to demonstrate that a strain-controlled, nonvolatile magnetization switching should be possible in appropriately engineered ferromagnetic/piezoelectric actuator hybrids.