Magnetic and magneto-optical properties of Pd/Cr/Co multilayers

Recent studies found that the (Pt/Co/Pt) trilayers can be used as a unit in combination with nonmagnetic or magnetic layer, X (X = Pd, Ag, Cu, and Ni) , to enhance the perpendicular magnetic anisotropy of the films, reduce the Curie temperature, and alter the magneto-optical properties. The effects o f intercalating Cr into Pd/Co multilayers on the magnetic and magneto-optic al properties are studied in this article. The perpendicular magnetic aniso tropy K-u and the coercivity H-c of the system decrease rapidly with increa sing the Cr thickness (X-Cr) up to 0.4 nm, and change slightly when Cr thic kness further increases. The dependence of the coercivity H-c on the Cr thi ckness, which obeys the law: H-c (X-Cr) = X-Cr(-2.66), indicates that the m agnetization reversal is controlled by domain wall moving, mainly due to th e interface roughness. Large decrease of the Kerr rotation theta (k) of the Pd/Cr/Co multilayers compared with pure Pd/Co multilayers is also found in the wavelength ranging from 200 to 800 nm. As it is well known, the large anisotropy and Kerr rotation in Pd/Co system are mainly caused by the polar ization of Pd atoms due to nearby Co atoms. As the intercalating of Cr laye r between Pd and Co layer, the average polarization of Pd atoms will be red uced largely. As a matter of fact, the Cr atoms can also be polarized by ne arby Co atoms, which, however, seems to take a minor effect on the anisotro py and Kerr rotation of the system. (C) 2001 American Institute of Physics.