Magnetisation reversal dynamics in an ultrathin magnetic film and the creep phenomenon

Effect of electrical current pulses on domain walls in Pt/Co/Pt nanotracks with out-of-plane anisotropy: Spin transfer torque versus Joule heating

“…Propagation velocities are thus considerably enhanced. [34][35][36][37] Besides, the Curie temperature, T C , of the material is reduced from 415 to 365 K. 28,34,35 The width of the tracks, patterned by a conventional process of e-beam lithography and ion-beam etching through a gold mask, was measured by scanning electron microscopy. For the track described in the following ͓Fig.…”

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

“…Before patterning, the films were uniformly irradiated at very low doses of 4 to 5 × 10 15 He + cm −2 , with an energy of 30 keV. This irradiation resulted in a strong reduction of the out-of-plane magnetic anisotropy [11,14], and, consequently, of the coercive and domain-wall-propagation fields [5,14,15]. The widths of the tracks described in the following range from 500 to 750 nm, for a typical length of 100 µm.…”

Pinning of domain walls in thin ferromagnetic films

“…Weak pinning may result from spatial fluctuations of domain wall energy associated to inhomogeneous thickness in ultrathin metallic films 4 , or concentration of magnetic atoms in ferromagnetic semiconductors 8 . As pinning impedes to reach the high velocity flow regimes, several attempts have been proposed to reduce the pinning strength finding low pinning materials 9 and to engineer the pinning properties using light-ion irradiation [9][10][11][12][13] in ultrathin films, or coupling with another magnetic layer 14 . Interestingly, the engineering of pinning is also important for superconducting materials 15,16 and a large variety of methods were developed to enhance the pinning strength on vortices.…”