ИСТИНА

X-ray absorption spectroscopy at Fe and Al K edges together with synchrotron-based diffraction has been applied to probe Fe and Al local environment and Al electronic structure in bare Fe60Al40 films of 40 nm thickness through the order-disorder (B2 → A2) phase transition initiated by 20keV Ne+ irradiation with low fluences (~1014 ions·cm-2). In the course of the transition distinct changes of Fe and Al coordination have been found and related to formation of Fe-rich regions due to inhomogeneous disordering created by ions. As a result, visibly increased 4p and 3d Fe polarizations with a characteristic fluence dependence have been found by XMCD technique at the Fe K and L2,3 edges, respectively. Furthermore, strong variations in coercive fields depending on temperature and irradiation fluence have been revealed by elementspecific hysteresis loops recorded at the Fe L3 edge. To reduce the unfavorable top oxide layer and to uncover a specific shoulder related to hybridization effects between Fe and Al an inductively coupled hydrogen plasma has been performed in-situ. Depending on the time of treatment an increase or decrease of Fe 3d spin magnetic moments in the surface region has been found. The former suggests that a use of a capping layer could further enhance the macroscopic magnetization of films which is more attractive for technological applications. A theory support was provided by self-consistent DFT calculations using VASP program package.