Magnetization of Amorphous<i>Co</i>P Alloy—Spin Waves in Noncrystalline Ferromagnets

Abstract

The Magnetization of several bulk amorphous ferromagnetic CoP alloys is shown to obey a corresponding-states law which differs significantly from comparable crystalline ferromagnets such as Co or Ni. This difference originates in an anomalously large ${T}^{\frac{3}{2}}$ low-temperature demagnetization extending beyond $0.2{T}_{C}$. The temperature and field dependence of this term provide evidence for the presence of spin-wave excitations characterized by a high density of states at low energies.