Excitation of Magnetic Domain Wall Velocity in (Co/Ni) Nanowires Induced by Blocking the Motion of Vertical Bloch Lines

The Dzyaloshinskii-Moriya interaction (DMI) has been a great attention in the magnetic domain wall (DW) motion [1]-[4]. It has been reported by the theoretical analysis that the DMI produces an effective chiral field that stabilizes Néel type walls, leading to efficient coherent motion (the steady motion) much faster than the DW velocity of several hundred at the Walker field (Hw) [1], [2]. In these reports, they have studied the DW motion around the H
_w
, however they have not discussed the DW motion in a high field region in which it is moved with the precessional motion. In the region, the DW velocity is affected by fluctuations of DW shape [5], and the vertical Bloch lines (VBLs) are nucleated and moved on the DW. In this report, we perform micromagnetic simulations and investigate the field-driven DW motion in a (Co/Ni) nanowire under the DMI, in particularly, in the high field region where is much higher than the Hw.