Wide-scale evolution of magnetization distribution in ultrathin films

Abstract

We show, combining simulations and analytical study, the evolution of magnetization distributions in ultrathin film with in-plane fields ${(H}_{\ensuremath{\parallel}})$ and changes of magnetic anisotropy characterized by the quality factor, Q. Reconstruction of the distributions and their new types near Q or ${H}_{\ensuremath{\parallel}}$-induced reorientation phase transitions, from a domain structure (DS) with perpendicular magnetization into a state with in-plane magnetization, are reported. Sinusoidal-like DS exist for ${H}_{\ensuremath{\parallel}}$ larger than the anisotropy field and for $Q<1.$ A minimal $8\ensuremath{\pi}{l}_{\mathrm{ex}}$ DS period is predicted ${(l}_{\mathrm{ex}}$ is the exchange length).