The energy of magneto-elastic materials is described by a nonconvex functional. Three terms of the total free energy are taken into account: the exchange energy, the elastic energy and the magneto-elastic energy usually adopted for cubic crystals. We focus our attention to a one dimensional penalty problem and study the gradient flow of the associated type Ginzburg-Landau functional. We prove the existence and uniqueness of a classical solution which tends asymptotically for subsequences to a stationary point of the energy functional.
Si studia il funzionale non convesso che descrive l'energia di un materiale magneto-elastico. Sono considerati tre termini energetici: l'energia di scambio, l'energia elastica e l'energia magneto-elastica generalmente adottata per cristalli cubici. Si introduce un problema penalizzato monodimensionale e si studia il flusso di gradiente dell'associato funzionale del tipo Ginzburg-Landau. Si prova l'esistenza e la unicità di una soluzione classica che tende asintoticamente, per sottosuccessione, a un punto stazionario del funzionale dell'energia.
@article{BUMI_2008_9_1_1_197_0,
author = {M. Chipot and I. Shafrir and G. Vergara Caffarelli},
title = {A Nonlocal Problem Arising in the Study of Magneto-Elastic Interactions},
journal = {Bollettino dell'Unione Matematica Italiana},
volume = {1},
year = {2008},
pages = {197-221},
zbl = {1164.49013},
mrnumber = {2388004},
language = {en},
url = {http://dml.mathdoc.fr/item/BUMI_2008_9_1_1_197_0}
}
Chipot, M.; Shafrir, I.; Vergara Caffarelli, G. A Nonlocal Problem Arising in the Study of Magneto-Elastic Interactions. Bollettino dell'Unione Matematica Italiana, Tome 1 (2008) pp. 197-221. http://gdmltest.u-ga.fr/item/BUMI_2008_9_1_1_197_0/
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