Magnetic Anisotropy of Iron-Cobalt Ferrite Measured by Ferromagnetic Resonance

The magnetic anisotropy of iron-cobalt ferrite is studied by means of ferromagnetic resonance. The cubic magnetic anisotropy K 1 / M and the uniaxial magnetic anisotropy K T / M induced by heat treatment in magnetic field are measured in the temperature range between 70°C and 250°C. The secondary peak observed in the ferromagnetic resonance of iron-cobalt ferrite are explained by the domains having different orientation of uniaxial magnetic axis. From the experimental results g -factor of iron-cobalt ferrite is determined to be 2.86. The temperature dependence of g -factor has not been observed within limits of errors.