Stripe domain and enhanced resonance frequency in ferrite doped FeNi films.

Stripe domain (SD) structures of FeNi films were controlled by doping different concentrations of ferrite. With increasing concentration of doped ferrite, SD width decreases, which indicated that perpendicular magnetic anisotropy (H⊥) increases. SD disappears and bubble-like features are observed with doping ferrite at 32% due to large H⊥. The origin for the enhancement of H⊥ is exchange coupling between ferrimagnet and ferromagnet. Moreover, different doping concentrations of ferrite realize an increase of resonant frequency from 1.3 to 2.3 GHz. [ABSTRACT FROM AUTHOR]