Demagnetizing field dependent dynamic spin freezing model with random easy axes orientation in nanoparticles ensembles*

We investigate the dynamic freezing of magnetic ensembles with varied self-arrangement of constituent Zinc Ferrite nanoparticles in their hierarchical ensembles. The small angle X-ray scattering and small angle neutron scattering experiments provide the overall information of the arrangement of primary nanoparticles in their secondary hierarchical ensembles. The extensive study of dc magnetization reveals the prevalence of strength of dipolar interaction among the nanoparticles on the magnetic memory effect [arXiv: 1907.11116]. The enhancement in magnetic memory effect in both the Field-Cooling and Zero Field-Cooling conditions is observed in an ensemble having higher demagnetizing field resulting higher degree of randomness in easy axes orientation with spin-glassy state at low temperature range.