The universal shape of crackling noise

The Barkhausen noise emitted by ferromagnetic materials during the hysteresis cycle represents an important non destructive tool for material characterization, but it is also an exemple of a non-equilibrium critical phenomenon ruled by the dynamics of domain walls.  Power-law scaling of critical phenomena has been most powerful for predictions near a critical point. By averaging the individual noise pulses, however, universal scaling functions can extend the predictive power of scaling even far away from the critical point.

A paper is published online in Nature Physics on January 23, 2011. This work was supported by CNR through the short-term mobility program.
see: Universality beyond power laws and the average avalanche shape.

Stefanos Papanikolaou, Felipe Bohn, Rubem Luis Sommer, Gianfranco Durin, Stefano Zapperi, James P. Sethna
Nature Physics (2011) doi:10.1038/nphys1884