  We investigate dynamic hysteresis in ferromagnetic thin films with zigzag
domain walls. We introduce a discrete model describing the motion of a wall in
a disordered ferromagnet with in-plane magnetization, driven by an external
magnetic field, considering the effects of dipolar interactions and anisotropy.
We analyze the effects of external field frequency and temperature on the
coercive field by Monte Carlo simulations, and find a good agreement with the
experimental data reported in literature for Fe/GaAs films. This implies that
dynamic hysteresis in this case can be explained by a single propagating domain
wall model without invoking domain nucleation.
