Properties of a resonance mode, the existence of which is related to the amorphous structure, are reported. This mode, in addition to the uniform mode, was observed in ${\mathrm{Co}}_{93\mathrm{-}\mathrm{x}}$${\mathrm{Zr}}_7$(R${)}_{\mathrm{x}}$ (R=Pr, Nd, Dy, Tb) amorphous thin films possessing an in-plane uniaxial anisotropy field ${\mathrm{H}}_{\mathrm{k}}$. A study as a function of the working frequency shows that when the magnetic field H is applied in the plane defined by the film normal and ${\mathrm{H}}_{\mathrm{k}}$, the mode can be identified as a longitudinal resonance, so detected even for H∥${\mathrm{h}}_{\mathrm{rf}}$∥${\mathrm{H}}_{\mathrm{k}}$. The mode is localized and this localization is 'stronger' for higher working frequencies so that the resonance fields are higher.

DOI:https://doi.org/10.1103/PhysRevB.55.11076