Effect of packing fraction on ferromagnetic resonance in NiFe2O4 nanocomposites

TitleEffect of packing fraction on ferromagnetic resonance in NiFe2O4 nanocomposites
Publication TypeJournal Article
Year of Publication2012
AuthorsSong, H., S. Mulley, N. Coussens, P. Dhagat, A. Jander, and A. Yokochi
JournalJournal of Applied Physics
Date Published03/2012
Keywordsdemagnetisation, ferromagnetic materials, ferromagnetic resonance, magnetic anisotropy, magnetic particles, nanocomposites, nanofabrication, nanomagnetics, nanoparticle, nickel compounds

Magnetic nanocomposites, composed of magnetic nanoparticles in an insulating matrix, can have properties not achievable in bulk, single-phase materials. This work reports on ferromagnetic resonance (FMR) measurements as a tool to investigate the internal magnetic field in nanocomposite samples of varying particle packing fractions. The ferromagnetic resonance frequency changes with particle packing fraction due to increased inter-particle interaction and demagnetizing field within the sample. Experimental results obtained on NiFe₂O₄ nanocomposite samples are compared to published theoretical models, and found to be consistent with the predicted trends. Extrapolation of the results to the limit of isolated particles indicates an average internal anisotropy field of 0.041 T for the NiFe₂O₄ nanoparticles.

Short TitleJ. Appl. Phys.