Dependence on Heat-treatment of the Ferromagnetic Resonance Width in Ni Ferrite

The ferromagnetic resonance absorption in Ni ferrite is observed at 9300 MC. The single crystal specimen is prepared by PbO flux method, and has the composition Ni 0.96 Fe 2.04 O 4 . The experiments are made repeatedly on one and the same specimen after various heat-treatments. The width, anisotropy constants, and g -factor change appreciably by the treatments. The results can be accounted for qualitatively to some extent, as caused by the change in the spinel phase itself or by the effect of precipitation. The minimum width obtained of 15 Oe is far narrower than that reported previously for the ferrites.