Enhanced Anisotropic FMR Linewidths Under Rotating Magnetic Fields in Fe-Si(001) Single-Crystal-Film Planes

In the material design of microwave assisted magnetic recording systems, fundamental properties about ferromagnetic resonance (FMR) must be indispensable for highly efficient magnetization switching. A paper reported that the wide and narrow FMR linewidths were observed when the magnetization pointed in the hard-axis (H.A.) and the easy-axis (E.A.), respectively [1]. In contrast, the FMR measurements for the 40-nm-thick Fe ${}_{100-x}\text{Si}_{x} \ \ (x=0, \ 6, \ 10)$ single-crystal-films with (001) orientation [2] revealed the additionallinewidth enhancement behaviours near H.A. The present study is intended to discuss the angular dependence of FMR linewidth $(\Delta H)$ in the films.