Abstract:
The soft magnetic properties and effective damping parameters of Fe₇₃Co₂₅Al₂ alloy thin films are discussed. The effective damping parameter α_eff measured by ferromagnetic resonance for the 10 nm-thick sample is nearly constant (≈0.004 ± 0.0008) for a growth temperature T_s from ambient to 200 °C, and then tends to decrease for higher temperatures and α_eff is 0.002 ± 0.0004 at T_s = 300 °C. For the 80 nm-thick sample, the α_eff seems to increase with T_s from α_eff = 0.001 ± 0.0002 at T_s = ambient to α_eff = 0.002 ± 0.0004. The α_eff is found nearly constant (α_eff = 0.004 ± 0.0008) over a temperature range from 10 to 300 K for the 10 nm films with the different T_s (ambient, 100 and 200 °C). Together with an increasing non-linearity of the frequency dependence of the linewidth at low T_s, extrinsic contributions such as two-magnon scattering dominate the observed temperature dependence of effective damping and linewidth.
