Hysteresis and after-effects in massive substances. From spin-glasses to the sand hill

摘要: We discuss the problem of magnetic hysteresis in framework a model distribution thermally activated double well potentials. Having shown equivalence, at T=0, this description with classical picture Preisach and Neel we consider specifically effects associated fact that width barrier-heights is necessarily finite. show how limit can be introduced construction it opens door to after-effects (in terms time temperature) as effect field beyond Rayleigh domain. describe detail evolution different loops remanences susceptibilites field, temperature. A particular reference made spin-glass case. The magnetization relaxations temperatures (S(T) curves) Fulcher law are discussed. finally attempt justification within language more adapted great generality which successfully applies mechanical or weight sand hill! !... This could viewed first-order approach non ergodic problems Analyse du probleme de l'hysteresis magnetique dans le cadre d'un modele d'etats deux niveaux actives thermiquement. Equivalence cette T=0 avec celle utilisee classiquement par et Neel. Etude des effets associes la largeur necessairement finie hauteurs barrieres. Description trainage en fonction temps temperature, champ hors domaine Rayleigh. Evolution cycles d'hysteresis champ, particulier pour les verres spin