Spin reorientation transition of ferromagnetic nanowires with perpendicular magnetic anisotropy

Abstract

We present an analytic theory of the magnetization phase in ferromagnetic nanowires with perpendicular magnetic anisotropy. In nanowire geometry, the shape anisotropy is reduced considerably in contrast to continuous films. Consequently, the spin reorientation transition occurs from in plane to out of plane with respect to the wire width. The stable domain size in the out-of-plane phase is sensitive to the wire width and approaches the single domain state on narrowing the width further. A phase diagram of the three phases is proposed with respect to the wire width and the saturation magnetization.