Relaxation of magnetic domain structure in garnet thin film under field cycles

A relaxation process of magnetic domain structure in a garnet thin film under field cycles have been investigated. Usually observed labyrinth structures contain many eddies. These labyrinth structures change to parallel-stripe structures under field cycles. In this evolution, eddy structures disappear. This process is evaluated by using a power spectrum analysis of the domain pattern. A number of magnetic domain junctions are introduced as another characteristic of complexity. These junctions are defined as a point, where magnetic domains with same direction intersect like a fork in the road. It is found that the number of junctions decrease with the power law as a function of the number of magnetic field cycles.