Barkhausen avalanches in anisotropic ferromagnets with $180^\circ$ domain walls

Bosiljka Tadic; Ulrich Nowak

doi:10.1103/physreve.61.4610

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Barkhausen avalanches in anisotropic ferromagnets with $180^\circ$ domain walls

Bosiljka Tadic·Ulrich Nowak

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Abstract

We show that Barkhausen noise in two-dimensional disordered ferromagnets with extended domain walls is characterized by the avalanche size exponent $τ_s =1.54$ at low disorder. With increasing disorder the characteristic domain size is reduced relative to the system size due to nucleation of new domains and a dynamic phase transition occurs to the scaling behavior with $τ_s=1.30$. The exponents decrease at finite driving rate. The results agree with recently observed behavior in amorphous Metglas and Fe-Co-B ribbons when the applied anisotropic stress is varied.

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BibTeX RIS

Bosiljka Tadic, Ulrich Nowak. 2000-01-12. Barkhausen avalanches in anisotropic ferromagnets with $180^\circ$ domain walls. https://doi.org/10.1103/physreve.61.4610

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