Bubble-domain lattices in the vicinity of the compensation point

The behavior of a hexagonal lattice of bubble domains in thin uniaxial films of garnet ferrites is studied in the temperature range from the compensation point to the Néel temperature. Two types of first-order phase transitions (preserving and not preserving the total number of domains in the bubble-domain lattice) occurring with variation of the temperature were studied. It is shown that the type of a phase transition is determined by the temperature dependence of the characteristic length of the film. The existence of two types of phase transitions is explained in terms of magnetostatic pressure existing in a bubble-domain lattice.