Micromagnetic Studies on Stripe Domain in Soft-Magnetic Thin Films

In this paper, the influence of the magnetostriction effect on the formation of the stripe domain is studied by micromagnetic simulations. The microstructures and local stress are carefully investigated in soft-magnetic thin films with a thickness from 2 to 256 nm. The domain structures, as well as the M-H loops, of these thin films are calculated by applying the in-plane periodic boundary conditions. It is found that a critical angle phi(0), which is the minimum angle between the magnetoelastic fields H-ms in neighbor stripes, exists for the formation of the stripe domains in a thin film. Furthermore, phi(0) depends on the maximum angle between the H-ms and the boundary line of neighbor stripes. The second-order derivative of the vertical component of the magnetic stray field which corresponding to the magnetic force microscope signal is also simulated. The M-H loop is calculated in a large thin film with an assumption that the stripe domains are isotropic in-plane. The shapes of these hysteresis loops can also be an indicator of the stripe-domain configuration.