NONLINEAR DYNAMICS OF THE MAGNETIZATION IN AN ANISOTROPIC FERROMAGNETWITH A MAGNETIC-FIELD

Introducing a particular parameter in the equations of motion for the magnetization in an anisotropic ferromagnet with a magnetic field, the Lax equations for Darboux matrices are generated recursively, the Jos t solutions are satisfied the corresponding Lax equations, and the non linear dynamics of the magnetization are investigated. The results sho w that the solitary waves depend essentially on two velocities which d escribe a spin configuration deviating from a homogeneous magnetizatio n. The center of inhomogeneity moves with a constant velocity, while t he shape of solitary waves also changes with another velocity. The dep ths and widths of surface of solitary waves vary periodically with tim e, meanwhile its shapes are not symmetrical with respect to the center . The z component of the total magnetic moment and the total magnetic moment are not constants. The asymptotic behavior of multisoliton solu tions is also analyzed.