Kerr rotations and anisotropy in (Pt/Co/Pt)/X multilayers

The link between interface sharpness and perpendicular magnetic anisotropy (K/sub /spl perp//) in Pt/Co multilayers has been exploited to yield enhanced magnetic anisotropy in related multilayer structures. These new multilayers consist of a (Pt/Co/Pt)/Pd stacking sequence where the Pt thickness is of just one atomic monolayer. The extra interfaces per period are introduced in areas where the spin polarization is still expected to be large thus resulting in extra magnetic anisotropy. K/sub /spl perp// as high as 5/spl times/10/sup 7/ erg/cm/sup 3/ was measured in Xe sputtered films with this new period. This idea was extended to (Pt/Co/Pt)X systems with X=Ag, Cu, Ni. A ten fold increase in K/sub /spl perp// is observed in these films compared to their respective Co/X counterparts. The Kerr rotation (/spl theta/K) as a function of photon wavelength is also greatly enhanced by the presence of the Pt monolayers. A strong dependence of /spl theta/K on the spacer element X in these systems is observed.