Dynamic magnetostatic interaction between amorphous ferromagnetic wires

The axial hysteresis loop of highly magnetostrictive amorphous wires shows a perfect square shape, with a single large Barkhausen jump due to its particular domain structure. When wires of this type are placed in proximity, the corresponding axial hysteresis loop exhibits a number of Barkhausen jumps equal to the number of wires, the form of the loop not being stable in time. We analyze this type of loop as resulting from magnetostatic interaction among the wires. The instability of the loop results from the lack of simultaneous magnetization reversal in each wire when the magnetic field is applied. This unstable behavior is interpreted considering the theory of chaos.