Topological ‘‘melting’’ of cellular domain lattices in magnetic garnet films

Abstract

We report observations of order-disorder phase transitions in metastable cellular patterns of magnetic domains at room temperature. The advance of a front destroys an ordered hexagonal domain lattice and leaves a topologically disordered cellular phase. Front motion is driven by stress in the domain patterns induced by an external bias field. The topological nature of the transitions gives rise to the novel features of particle (cell) nonconservation and irreversibility.