Magnetic properties of magnetite nanowire arrays

Abstract

The contributions of isolated Fe3+ ions and the ferrimagnetic subsystem to the total magnetization of Fe3O4 nanowires were separated. The magnetic anisotropy of nanowires was determined. The value of the magnetic anisotropy is smaller than the expected value of the shape anisotropy. The decrease in the magnetic anisotropy in nanowires can be explained by the dipole-dipole interaction between individual nanowires in the array. The Verwey transition suppression was found. A phase-inverted line corresponding to the microwave magnetoresistance was identified in the electron spin resonance spectra of nanowires.