High-field magnetization curve of random-anisotropy amorphous magnet: Observation of a crossover and link to structural short-range order

High-field magnetization curves of the series of amorphous alloys ${\mathrm{Dy}}_{\mathit{x}}$ ${\mathrm{Gd}}_{1\mathrm{-}\mathit{x}}$Ni have been measured up to 15 tesla and interpreted in the framework of the theory of Chudnovsky et al. The results show several features (high-field crossovers, correlation volume of local-anisotropy directions, ferromagnetic correlation length) all consistent with each other and in agreement with theoretical predictions.