Two-dimensional domain-wall magnon waves in superconducting ferromagnets

Propagation of magnetization waves along domain walls (DWs) in a superconducting ferromagnet (SCFM) leads to electromagnetic (EM) absorption which provides a direct evidence of magnetic order coexisting with superconductivity. The influence of long-range dipole-dipole interaction on the spectrum of two-dimensional magnons is essentially affected by the superconducting Meissner currents, which screen the magnetostatic fields and modify the long-wavelength spectrum from square root to linear. The excitation of the DW waves by an EM wave incident on a SCFM sample has been considered. This suggests using measurements of the surface impedance for the study of the DW waves and, eventually, for an effective probing of superconductivity- ferromagnetism coexistence.