Influence of Heavy Ions on the Magnetic Properties of Fe₃O₄ Nanoparticles

The effect of heavy ions on the magnetic properties of Fe3O4 nanoparticles with d = 20-30 nm was studied. The magnetic properties were studied by vibrational magnetometry. It has been established that Fe3O4 nanoparticles have ferromagnetic properties under normal conditions and at room temperature. The value of the specific magnetic moment was determined: M = 33.4 emu/g. It has been established that under the influence of temperature, a decrease in the value of the specific magnetic moment in Fe3O4 nanoparticles is observed, at a temperature of T-C = 655 K, a ferromagnet-paramergrite phase transition occurs, and the value M = 0 is obtained. As a result of the study, the values of the specific magnetic moment and Curie temperature in Fe3O4 nanoparticles irradiated with a stream of fast heavy Xe-132 ions with an energy of 167 MeV at intensities of 4.14 x 10(12) ion/cm(2), 2.75 x 10(13) ion/cm(2) and 3.83 x 10(14) ion/cm(2). The mechanism of change of magnetic properties depending on radiation is determined.