Bending strain-tunable magnetic anisotropy in Co2FeAl Heusler thin film on Kapton

TL;DR

This study demonstrates that bending a Co2FeAl Heusler thin film on Kapton significantly alters its magnetic anisotropy due to strain transmission and magnetoelastic effects, with methods proposed to measure its magnetostriction coefficient.

Contribution

It introduces a novel approach to tune magnetic anisotropy via bending and provides two methods to determine the film's magnetostriction coefficient.

Findings

Magnetic anisotropy is drastically affected by bending.

Interfacial strain transmission influences magnetic properties.

Magnetostriction coefficient is estimated to be around 14×10^{-6}.

Abstract

Bending effect on the magnetic anisotropy in 20 nm Co$_{2}$FeAl Heusler thin film grown on Kapton\textregistered{} has been studied by ferromagnetic resonance and glued on curved sample carrier with various radii. The results reported in this letter show that the magnetic anisotropy is drastically changed in this system by bending the thin films. This effect is attributed to the interfacial strain transmission from the substrate to the film and to the magnetoelastic behavior of the Co$_{2}$FeAl film. Moreover two approaches to determine the in-plane magnetostriction coefficient of the film, leading to a value that is close to $\lambda^{CFA}=14\times10^{-6}$, have been proposed.