Magnetic properties of full-Heusler alloy Co2Fe1-xMnxAl films grown by molecular-beam epitaxy

We have investigated magnetic properties of single-crystalline full-Heusler alloy Co2Fe1-xMnxAl films (0 < x < 1) grown on GaAs (001) by molecular-beam epitaxy at different temperatures. It is found that as x increases, the films grown at 160 degrees C have complex magnetic phases, but show pure ferromagnetic properties when grown at 280 degrees C. We attribute this magnetic behavior to the competition between ferromagnetic and antiferromagnetic Mn-Mn interactions, which are proved by x-ray magnetic circular dichroism measurements. Moreover, we have investigated in-plane magnetic anisotropies of Co2Fe1-xMnxAl films with pure ferromagnetic phases and deduced the corresponding anisotropy constants which also remarkably depend on x. (C) 2010 American Institute of Physics. [doi:10.1063/1.3525376]