Effect of stress on the entropy calculated by applying the zipping method to Barkhausen noise

Abstract The effect of applied stress on the magnetization process of magnetostrictive Fe 78 B 13 Si 9 and amorphous Fe 73.5 Cu 1 Nb 3 Si 13.5 B 9 is investigated by calculating the entropy by means of the zipping method to the Barkhausen noise time series. The relative entropy is estimated as the size of the packed time series and is obtained by applying the LZ77 algorithm. Above a given stress level, an increase in the relative entropy is observed, possibly as a result of the decrease in the domain wall width. The results are compared with domain structure observations by Kerr microscopy and to magnetization curves obtained by the inductive method.