11. Degradation of domains with sequential field application

Nirvana Caballero

2021

Recent experiments show striking unexpected features when alternating square magnetic field pulses are applied to ferromagnetic samples: domains show area reduction and domain walls change their roughness. We explain these phenomena with a simple scalar-field model, using a numerical protocol that mimics the experimental one. For a bubble and a stripe domain, we reproduce the experimental findings: The domains shrink by a combination of linear and exponential behavior. We also reproduce the roughness exponents found in the experiments. Finally, our simulations explain the area loss by the interplay between disorder effects and effective fields induced by the local domain curvature.