Phase transitions in bubble domain structures upon spin reorientation near the compensation point in ferrite-garnet films

The behavior of a hexagonal lattice of bubble domains in a uniaxial thin film of (BiTm)₃(FeGa)₅O₁₂ ferrite garnet with a compensation temperature of 120 K was studied experimentally in a range of change in anisotropy from the easy magnetization axis to the easy magnetization plane. It is shown that the spin reorientation occurs in the temperature range 185–160 K, in which the angular phase (either (Phi _{leftlangle {1bar 1bar 1} rightrangle }) or (Phi _{leftlangle {bar 111} rightrangle })) and the axial phase Φ:_〈111〉 coexist. At 172 K, when the percentages of the angular and axial phases are equal, the lattice parameters of the bubble domains and the domain-wall width change stepwise. At T < 160 K, only a plane magnetic phase exists.