Film-cooling-induced phase transitions in magnetic bubble lattices

Abstract

A theoretical study of the transition taking place in magnetic bubble lattices (MBLs) on cooling the film has been performed. It is shown that, if the MBL was formed at room temperature, then, on cooling the film, spontaneous transitions occur from the initial MBL to a lattice with a larger domain period and diameter. The nature of these transitions is that of first-order phase transitions and they are accompanied by a change in the total number of domains in the specimen. The phase diagram or the MBL formed in thin bismuth-thulium garnet films is calculated; there is good agreement with experimental results.