Effects of exchange randomness on two-dimensional magnetic domain pattern formation

• Exchange randomness is introduced to the model of magnetic domain pattern formation.
• Hysteretic behavior shows crossover as the randomness increases.
• The crossover is observed also in the time evolution of the structure factor.

Magnetic domain pattern formation is known to be influenced by structural disorder. We perform numerical simulations using a model of two-dimensional magnetic domain pattern formation focusing on effects of exchange randomness. The model is a scalar model with exchange and dipolar interactions, which includes disorder in the exchange interactions. Morphological change of the patterns with the increase in the disorder is observed. The distribution of the local magnetization becomes broader with the increase of the disorder. For a definite realization of the randomness, many patterns can appear.