Periodic instantons and domain structure in a ferromagnetic film

We in this paper study periodic instantons and domain structures in a theoretical film consisting of biaxial-anisotropic ferromagnets. In a proper approximation the equation of motion of the magnetization vector as a space-time function in the film is reduced to the 1 + 2-dimensional sine-Gordon field equation in strong anisotropy limit. Static periodic instantons, which are solutions of Euclidean field equantion, and various new domain structures are obtained analytically. We also investigate the energy density and stability of the periodic instantons.Received: 6 August 2003, Published online: 8 December 2003PACS: 05.45.Yv Solitons - 75.70.Kw Domain structure (including magnetic bubbles)