We investigate the scaling properties of the Barkhausen effect by recording the noise in several soft ferromagnetic materials: polycrystals with different grain sizes and amorphous alloys. We measure the Barkhausen avalanche distributions and determine the scaling exponents. In the limit of vanishing external field rate, we can group the samples in two distinct classes, characterized by exponents tau = 1.50 +/- 0.05 or tau = 1.27 +/- 0.03, for the avalanche size distributions. We interpret these results in terms of the depinning transition of domain walls and obtain an expression relating the cutoff of the distributions to the demagnetizing factor which is in quantitative agreement with experiments.
Scaling exponents for Barkhausen avalanches in polycrystalline and amorphous ferromagnets / G. Durin, S. Zapperi. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 84:20(2000), pp. 4705-4708.
Scaling exponents for Barkhausen avalanches in polycrystalline and amorphous ferromagnets
S. Zapperi
2000
Abstract
We investigate the scaling properties of the Barkhausen effect by recording the noise in several soft ferromagnetic materials: polycrystals with different grain sizes and amorphous alloys. We measure the Barkhausen avalanche distributions and determine the scaling exponents. In the limit of vanishing external field rate, we can group the samples in two distinct classes, characterized by exponents tau = 1.50 +/- 0.05 or tau = 1.27 +/- 0.03, for the avalanche size distributions. We interpret these results in terms of the depinning transition of domain walls and obtain an expression relating the cutoff of the distributions to the demagnetizing factor which is in quantitative agreement with experiments.File | Dimensione | Formato | |
---|---|---|---|
PhysRevLett.84.4705.pdf
accesso aperto
Tipologia:
Publisher's version/PDF
Dimensione
167.2 kB
Formato
Adobe PDF
|
167.2 kB | Adobe PDF | Visualizza/Apri |
Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.