IFIMAR 20926
INSTITUTO DE INVESTIGACIONES FISICAS DE MAR DEL PLATA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Barkhausen effect in ferromagnetic thin films (oral)
Autor/es:
R. C. BUCETA; D. MURACA
Lugar:
La Plata
Reunión:
Conferencia; HK 2010 - Humboldt Kolleg International Conference on Physics; 2011
Institución organizadora:
Humboldt Foundation - Universidad Nacional de La Plata
Resumen:
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The Barkhausen jumps (or avalanches) of magnetic domain-walls [MDW] between succesive pinned configurations, due the competition among magnetic external driving force and substratum quenched disorder, appear in bulk materials and thin films. For ferromagnetic thin films with exchange (or short-range) interactions, we introduce a model based in rules for the MDW evolution, that include disorder and driving force effects. We simulate in 2-dimensions with Monte Carlo dynamics, calculate numerically distributions of sizes and durations of the jumps and find power-law critical behavior. The jump-size exponent is compared with experimental results for thin films and other models, such as like random-field and random-bond disorder, or functional renormalization group. The model allows us to review current issues in the study of avalanches of the MDW in thin films with ferromagnetic interactions and opens a new approach to describe these materials with dipolar (or long-range) interactions.
