Full Heusler Fe2CrAl nanogranular films produced by pulsed laser deposition for magnonic applications

Abstract

Obtaining Heusler alloys at the nanoscale with good crystallographic features is appealing for a large range of technological applications, from biomedical to spintronics devices. In particular, Fe2CrAl as bulk is known to present magnetic properties that are strongly sensitive to chemical and physical constraints, such as structural disorder and chemical composition. We report a throughout structural, morphological, and magnetic characterization of Fe2CrAl Heusler nanoparticles obtained by pulsed laser deposition technique. The nanoparticles are composed of slightly off-stoichiometric grains with two distinct morphologies where the role of chemical disorder and inhomogeneity on the magnetic behavior was evaluated. Through DC magnetization measurements, a superparamagnetic behavior is observed and a Gilbert damping of 9×10−3 is acquired from broadband ferromagnetic resonance data, which is comparable with standard materials used for magnonics applications. We discuss the complex magnetostructural coupling that rises on the nanoparticle system, comparing these results with the stoichiometric Fe2CrAl bulk target behavior.