ON SPIN-WAVE SCATTERING BY A SOLITON IN A 2-DIMENSIONAL ISOTROPIC FERROMAGNET

Scattering of magnons by a two-dimensional topological Belavin-Polyako v soliton in an isotropic ferromagnet is studied analytically. It is s hown that the problem of spin wave scattering by a soliton with an arb itrary value of the topological charge nu can be analyzed completely i n the longwave limit. General principles of the soliton-magnon interac tion are studied, especially the relation between scattering and the b ehavior of the mode as the magnon wave vector k approaches zero. It is found that the scattering intensity has its maximum value for partial waves with the azimuthal number m = 0, +/- 1, +/- 2 (m = nu - 1). Alt hough the mode with the maximum scattering always passes to a local mo de for k --> 0 according to the general law, this fact is not crucial for the scattering intensity. In particular, the scattering intensity is stronger for a partial wave with m = -1 for nu = 1 (there is no loc al mode for k --> 0) than for a partial wave with m = +1 (a local mode exists for k --> 0). (C) 1998 American Institute of Physics. [S1063-7 77X(98)01107-4].