Size and interaction effects in the magnetization reversal in SmCo 5 nanoparticles

The switching field distribution found from DC demagnetization experiments on ball milled SmCo₅ nanoparticles is analysed in terms of several mechanisms for magnetization reversal. By combining the log-normal size distribution with the size-dependent coercivity predicted for different models, switching field distributions are calculated and compared to the experimental results. None of the size-dependent models alone agrees with the Gaussian shape or the linewidth of the experimental data. However, statistically distributed interactions between particles could explain the deviations