Vortex pinning in superlattices of ferromagnetic and nonmagnetic superconductors

Vortex pinning in superlattices composed of the layers of ferromagnetic and nonmagnetic superconductors is studied theoretically. The critical pinning-force density p/sub c/ is calculated as a function of the flux density using the free energy of the mixed state in the superlattices. p/sub c/ is greatly enhanced by the electromagnetic interaction between the vortex current and magnetic moments in the layers of ferromagnetic superconductor. The possibility of high supercurrent capacity in the superlattices is discussed.