Effect of the Vortex Structure on the Ground State and the Magnetostatic-Wave Spectrum of a Uniaxial Ferromagnetic Film with Superconducting Covering

摘要

For the case of a uniaxial ferromagnetic film with one-sided superconducting covering in a tangential external magnetic field, the effect of the vortex structure of a superconductor on the transition from uniform to nonuniform states of the ferromagnetic film is considered as a function of the film thickness. It is shown that the critical thickness of the magnetic film for which nonuniform states become energetically disadvantageous strongly depends on the degree of pinning of the vortices in the superconductor. It is established that, for sufficiently thin magnetic layers, the interaction between the magnetic and vortex subsystems may change the type of transition from a collinear to a domain phase. A vortex correction to the dispersion and attenuation of magnetostatic waves is calculated as a function of the external field, wave frequency, and the vortex-pinning constants.