Fig. 3: Domain wall (DW) dynamical properties.
From: Walker-like domain wall breakdown in layered antiferromagnets driven by staggered spin–orbit fields
a Spatiotemporal evolution of the magnetisation. Inset represents the domain walls, DW1 and DW2 initial oscillations before reaching a stable distance between them. The separation is due to the competition between the Zeeman energy, EZee, provided by the spin–orbit field, \({\overrightarrow{H}}_{\text{so}}\), which tries to pull them closer while the exchange energy, Eexc, tries to separate them as both DWs have the same winding number. b Stable distance between DW1 and DW2 of 29 nm calculated for an applied \({\overrightarrow{H}}_{\text{so}}\) = 65 mT. c DW1, DW2 and DW3 velocity as a function of time. At the moment the nucleation starts, the maximum registered speed of DW3 travelling at supermagnonic speeds is 177 km/s. When DW1 and DW2 are fully formed, DW3 propagates at 133 km/s. A smooth recovery of DW3 towards submagnonic speeds is observed and lasts for about 100 ps. d Phase, vph, and group velocity, vg, of the magnons as a function of the wave-vector, k, for an applied \({\overrightarrow{H}}_{\text{so}}\) = 65 mT extracted from the dispersion relation. Notice that once DW3 enters into the supermagnonic regime of motion it also surpasses the phase velocity of the magnons which is manifested by the spin-Cherenkov radiation.
