Density of magnetic poles in amorphous ferromagnetic wires: An example of weak chaos

While a single piece of Fe-base amorphous wire is well known to exhibit square hysteresis loop, it is experimentally shown here that when placing a set of n quasi-identical amorphous Fe-base wire its hysteresis loop consists of n large Barkhausen jumps separated by (n−1) horizontal stretches. This kind of loop is interpreted as arising from the magnetic interaction among wires. Each wire is considered to have a particular density of magnetic poles at the ends creating an additional field at its neighborhood. Such a density arises from the closure domain structure at the ends which is slightly modified after each reversal. These magnetic interactions are analyzed and proven to induce a weak chaotic behavior for the switching field of each single wire.