EXCESS RESISTANCE AND COLLECTIVE MOTION OF FERROMAGNETIC DOMAIN-WALLS IN AMORPHOUS FE5.85 CO72.15 MO2 B-15 SI5 RIBBONS TRAVERSED BY DC ELECTRIC CURRENTS

The reversal of the Hall voltage across a ferromagnetic domain wall drives a dc eddy-current loop centered on the wall in metallic samples traversed by a dc current. The Joule dissipation in the loop leads to an additional ohmic resistance associated with walls, the 'excess resistance' delta R. Field-annealed ribbons with in-plane magnetization normal to sample length are considered. The excess resistance delta R has been measured at 300 K by removing all walls with a saturating field parallel to the domain magnetization, and looking for the corresponding decrease of resistance. The measured delta R values agree within a factor of two with theoretical predictions.