Dependence of normal and reversed gyroremanent magnetization on ac field strength in participate media

In this paper we present experimental results of the dependence of gyroremanent magnetization (GRM) on AC field strength for both "normal" and "reversed" GRM. The experiments were performed on samples of whole tape containing ?Fe₂O₃ particles, as well as samples containing dilutely dispersed ?Fe ₂O₃ particles set in resin, to highlight any differences due to particle interactions. The dispersed particles also had differing degrees of anisotropy, so that any potential differences due to intrinsic anisotropy could also be determined. The results were also compared with recent data on dilutely dispersed CrO₂ particles.