Effect of the strong relaxer cobalt on the parallel and perpendicular pumping spin-wave instability threshold of LiTi ferrites

Abstract

Room temperature data on the parallel and perpendicular pumping instability threshold at 9.4 GHz, using a reflection-type microwave spectrometer, are reported for a series of polycrystalline LiTi ferrites substituted with the strong relaxing ion cobalt. The experimental instability threshold results show strong variation with cobalt substitution. The experimental butterfly curves are reproduced theoretically from the revised pore-scattering model, taking into account the k dependence of the spin-wave linewidth from a trial function: Δ H k = A + BΔ H k ( p) + Ck.