Ferromagnetic resonance in tunnel junctions: Mag-noise and complex impedance analysis

The ferromagnetic resonance (FMR) in the Co80Fe20/Ni80Fe20 free layer of micron-sized magnetic tunnel junction (MTJ) device was discussed. The correlations between magnetoresistance and FMR frequency versus in-plane magnetic field were found to be observed for different devices. The analysis showed that FMR frequencies agreed well with calculations when including substantial out-of-plane magnetic anisotropy fields.