AVALANCHES AS PROPAGATING DOMAIN-WALLS IN A MICROMAGNETIC MODEL

The ideas of self-organized criticality can be partially applied to de scribe collective demagnetization process. The basic point to proceed with this analysis is the identification of propagating domain walls w ith avalanches. We study the avalanche size distributions in a microma gnetic model describing a textured polycrystal. For small size systems ive have found the distribution functions span!ling a range equivalen t to the system size. Analogously to sandpile models, the ''subcritica l'' collective demagnetization process has been also observed. Copyrig ht (C) 1998 Elsevier Science B.V.