Magnetic interaction of submicron-sized ferromagnetic rings in one-dimensional array

摘要

Magnetization characteristics of submicron-sized ferromagnetic rings in a one-dimensional array with various inter-ring distances, l_x, were investigated by the magneto-optical Kerr effect and micromagnetic simulation. The onion (vortex)-to-vortex (onion) transition fields were found to be proportional to 1/l_x~n with n = 1.36 (0.79), instead of being a simple dipole interaction model (n = 3). It was demonstrated that the transition mechanism and the inter-ring dependence are governed by the energy gain originating from the deformation of the local vortex. As a result, exchange energy as well as magnetostatic energy play important roles in the magnetization reversal of ring array.