ACOUSTIC SOLITON IN ONE-DIMENSIONAL FERROMAGNETIC SYSTEMS

The local nonlinear excitation caused by the magnon-phonon interaction s as an anisotropic source of nonlinearity is studied. The nonlinear e quation for the Schrodinger probability amplitude of spin motion is gi ven, and its soliton solutions are obtained in a weak coupling approxi mation. The existence conditions are discussed. It is shown that the s oliton excitation energy can be less than a one-magnon state and a gap appears in the energy spectrum. The effect of the magnon-magnon inter actions on the local acoustic soliton excitation is also discussed.