Nanoscale measurement of giant saturation magnetization in α″-FeN by electron energy-loss magnetic chiral dichroism.

Metastable α″-FeN thin films were reported to have a giant saturation magnetization of above 2200 emu/cm in 1972 and have been considered as candidates for next-generation rare-earth-free permanent magnetic materials. However, their magnetic properties have not been confirmed unequivocally. As a result of the limited spatial resolution of most magnetic characterization techniques, it is challenging to measure the saturation magnetization of the α″-FeN phase, as it is often mixed with the parent α'-FeN phase in thin films.