Spin-configuration-related ferromagnetic resonance in nickel nanowire array

The angular dependence of specific precession modes of an Ni nanowire array in the magnetization process was thoroughly investigated by ferromagnetic resonance. Compared with the uniform precession mode in near-saturated states, additional resonance was observed at low applied fields when the field orientation diverged from the wire axis. The origin of such a low-field resonance is discussed in detail in the transverse magnetization case. The particular resonances were considered from the spin precession in remanent longitudinal domains in the unsaturated states of the nanowires, which gave strong experimental evidence of a nucleation mode in the magnetization process of the nanowire array.