Strong perpendicular magnetic anisotropy in [Co/Pt]n ultrathin superlattices

Abstract Ultrathin [Co/Pt] n superlattice films consisting of 0.18–0.60-nm-thick Co and Pt sublayers were deposited by sputtering. A large in-plane saturation field ( H s ) of ∼39 kOe and a very large effective perpendicular magnetic anisotropy ( K eff ) with a magnitude of 10 7 erg/cm 3 were attained. The highest K eff was ∼1.40 × 10 7 erg/cm 3 . These films are promising candidates for the reference layer of the p-MgO magnetic tunnel junction in Gb-scale magnetic random-access memory.