Pinning of a Bloch wall by diffusion of carbon atoms in a silicon-iron single crystal: an experimental study by means of an autoregressive spectrum analysis method

Diffusion of interstitial C atoms in Fe creates the phenomenon of the "diffusion after-effect". After a review of the main features of this effect, an experimental study of this phenomenon in a SiFe crystal is reported. The various waveshapes generated by the motion of a single Bloch wall are analysed by an autoregressive signal processing technique which allows the study of the "instantaneous" power spectrum. A simple model is proposed in order to account for the experimental results. 18 ref.--AA