Magnetic and structural anisotropies of Co2FeAl Heusler alloy epitaxial thin films

TL;DR

This study investigates the magnetic and structural anisotropies in epitaxial Co2FeAl Heusler alloy thin films, revealing three distinct in-plane anisotropies and their dependence on annealing temperature, linking chemical order and magnetic properties.

Contribution

It provides a detailed analysis of the different types of in-plane anisotropies in Co2FeAl films and their evolution with annealing, highlighting the interplay between chemical order and magnetic behavior.

Findings

Identification of three in-plane anisotropies: biaxial and two uniaxial.

Biaxial anisotropy increases monotonically with annealing temperature.

One uniaxial anisotropy decreases with annealing, the other remains constant.

Abstract

This paper shows the correlation between chemical order, lattice strains and magnetic properties of Heusler Co2FeAl films epitaxially grown on MgO(001). A detailed magnetic characterization has been performed using vector field magnetometery combined with numerical Stoner-Wohlfarth analysis. We demonstrate the presence of three types of in-plane anisotropies: one biaxial, as expected for the cubic symmetry, and other two uniaxial ones. The three anisotropies show different behavior with the annealing temperature. The biaxial anisotropy shows a monotonous increase. The uniaxial anisotropy, parallel with the hard biaxial axes, related to the chemical homogeneity, decreases, while the other, supposed to have magnetostatic origin, remains constant.