  Electric field effects in ferromagnetic/oxide dielectric structures provide a
new route to control domain wall (DW) dynamics with low power dissipation.
However, electric field effects on DW velocities have only been observed so far
in the creep regime where DW velocities are low due to strong interactions with
pinning sites. Here, we show gate voltage modulation of DW velocities ranging
from the creep to the flow regime in Ta/Co40Fe40B20/MgO/TiO2 structures with
perpendicular magnetic anisotropy. We demonstrate a universal description of
the role of applied electric fields in the various pinning dependent regimes by
taking into account an effective magnetic field being linear with the electric
field. In addition, the electric field effect is found to change sign in the
Walker regime. Our work opens new opportunities for the study and optimization
of electric field effect at ferromagnetic metal/insulator interfaces.

Materials Science;Mesoscale and Nanoscale Physics;Applied Physics