Fast propagation of weakly pinned domain walls and current-assisted magnetization reversal in He+-irradiated Pt/Co/Pt nanotracks

International audienceMagnetic-domain-wall propagation is experimentally studied in nanotracks etched in ultrathin Pt/Co/Pt films with out-of-plane magnetic anisotropy, where pinning has been artificially reduced by low-dose He + -irradiation. Fast domainwall propagation is demonstrated in such tracks under low magnetic fields, not greater than the fields necessary to make a domain wall propagate in the He + -irradiated plain films before patterning. A strong further enhancement of the track-magnetization reversal speed is obtained thanks to a Joule-heating-induced thermomagnetic effect, by applying magnetic-field and electrical-current pulses simultaneously to the track