Fe nanoparticles embedded in MgO crystals

Iron nanoparticles embedded in MgO crystals were synthesized by Fe+ ion implantation at an energy of 100 keV and varying fluences from 3×10e16 to 3×10e17 cm-2. Investigations of structural and magnetic properties of Fe nanoparticles have been performed using magnetometry, x-ray diffraction, transmission electron microscopy and Mössbauer spectroscopy, as well as by theoretical Preisach modeling of bistable magnetic systems. It has been found that alpha- and gamma-Fe nanoparticles are formed for all fluences. The content of the alpha- Fe phase increases at higher fluences and after annealing. The influence of post implantation annealing at 800 ºC in vacuum and under enhanced up to 10 kbar hydrostatic pressure in argon atmosphere on the formation of nanoparticles has been analyzed.