# Full Electroresistance Modulation in a Mixed-Phase Metallic Alloy

## TL;DR

This paper demonstrates a significant electroresistance change in a metallic alloy at room temperature, achieved through electric field-induced magnetic phase transition via strain coupling in heterostructures.

## Contribution

It provides experimental evidence of an isothermal magnetic phase transition driven by strain modulation in FeRh thin films, contrasting with traditional temperature-driven transitions.

## Key findings

- 22% electroresistance modulation at room temperature
- Electric field of 2 kV/cm induces magnetic phase transition
- FeRh acts as a mixed-phase system similar to phase-separated materials

## Abstract

We report a giant, ~22%, electroresistance modulation for a metallic alloy above room temperature. It is achieved by a small electric field of 2 kV/cm via piezoelectric strain-mediated magnetoelectric coupling and the resulting magnetic phase transition in epitaxial FeRh/BaTiO3 heterostructures. This work presents detailed experimental evidence for an isothermal magnetic phase transition driven by tetragonality modulation in FeRh thin films, which is in contrast to the large volume expansion in the conventional temperature-driven magnetic phase transition in FeRh. Moreover, all the experimental results in this work illustrate FeRh as a mixed-phase model system well similar to phase-separated colossal magnetoresistance systems with phase instability therein.