Isothermal remanence (IRM) induced in multidomain grains at a high temperature (T*) decreases on cooling in zero field. The intensity and stability (against temperature change) of the IRM depend on whether the temperature T* was reached from a higher temperature or from a lower temperature. These results cannot be explained by the existing multidomain theories. A new model of TRM (thermoremanence) acquisition mechanism in which domain wall interactions play the major role is proposed. This model explains the main features of the experimental results very well and predicts an almost linear relationship between TRM and the inducing field, up to relatively high fields.

You do not currently have access to this article.