Evolution of the magnetic hyperfine field profiles in an ion-irradiated Fe₆₀Al₄₀ film measured by nuclear resonant reflectivity

Nuclear resonant reflectivity (NRR) from an Fe 60 Al 40 film was measured using synchrotron radiation at several grazing angles near the critical angle of total external reflection. Using laterally resolved measurements after irradiation with 20 keV Ne + ions gradually varying fluence 0–3.0 × 10 14 cm −2 , progressive creation ferromagnetic A2 phase increasing ion confirmed. The observed depth selectivity method has been explained by application standing wave approach. From time spectra nuclear scattering in reflection directions profiles for different hyperfine fields were extracted. results show that highest magnetic (∼18–23 T) are initially created central part and partially bottom interface SiO 2 substrate. evolution onset, commencing a fixed within propagating towards interfaces, directly observed. At higher (3.0 ) distribution fractions became more homogeneous across depth, accordance previous results.