Interactions and hysteresis behaviour of Fe/SiO2 nanocomposites

Abstract We present a study of interactions in mechanically alloyed Fe/SiO2 nanocomposites. The ΔM plots and the switching field distributions reveal that increasing Fe concentrations lead to higher dipolar fields and larger dipolarly coupled regions. We propose a switching mechanism based on avalanche phenomena triggered by the reversal of individual particles, irrespective of the Fe concentration being above or below percolation.