Annealing Effect on Structural and Magnetic Properties of Cu2MnAl Heusler Alloy Films

Abstract

Cu2MnAl Heusler alloy films were grown on MgO (001) substrates by using the ion beam sputtering technique. The films were post-annealed at varying temperatures in order to investigate the influence of annealing on crystal structure and magnetic properties. The structural properties of Cu2MnAl films have been investigated by using x-ray diffraction (XRD) and magnetic properties have been investigated by both vibrating sample magnetometer (VSM) and ferromagnetic resonance (FMR) techniques. The experimental data indicates that the crystal structure of the films strongly depends on the annealing temperature. When the films were annealed at 200 A degrees C, the saturation magnetization (M (s) =250 emu/cm(3)) achieved its maximum and the coercive field (H (c) a parts per thousand 7 Oe) reached its minimum with B2 ordered structure. In addition, FMR results have revealed that the Cu2MnAl film annealed 200 A degrees C has the highest effective magnetization. The combination of structural and magnetic characterization indicates that the optimum growth temperature is 200 A degrees C for the Cu2MnAl Heusler alloy films on MgO substrates.