Maximum velocity of a domain wall in a weak ferromagnet
Chetkin M.V., de la Campa A.
The velocity of a straight-line domain wall in orthoferrite plates perpendicular to the optical axis is investigated. It is shown that dependence of the velocity on the amplitude of the pulsed magnetic field ceases to be linear when the velocity of the domain wall becomes equal to the velocity of the transverse sound, and exhibits saturation at velocities 2X104 m/sec. This saturation of the velocity is attributed to excitation of spin waves in the weak ferromagnet by the moving wall. A generalization of the formula for the maximum of the domain wall in a ferromagnet is obtained for the case of weak ferromagnets. The value 1.7X104 m/sec obtained from this formula for the maximum velocity is in qualitative agreement with experiment.