Superparamagnetism in heterogeneous AgFe thin films: A low energy μSR study

This paper describes a study of superparamagnetism in iron nanoclusters using low energy μSR, including for the first time zero field measurements, which yield an intrinsic nanocluster superparamagnetic relaxation rate ofv 0 = 67 ′ 15 MHz and an energy barrier of ΔE = 37 ′ 4 K. TEM micrographs of the embedded clusters show there to be a range of shapes and also sizes, which is bourne out by SQUID magnetometry measurements.