HALL-EFFECT STUDIES ON AR AND XE SPUTTERED PT CO MULTILAYER FILMS/

The extra-ordinary Hall effect has been studied in Ar sputtered Pt(x a ngstrom)/Co(5 angstrom) and Xe sputtered Pt(x angstrom)/Co(3 angstrom) multilayers with coercivity less-than-or-equal-to 8 kA/m and greater- than-or-equal-to 72kA/m at RT, respectively. The Hall resistivity-rho( H) was found to be larger and have a different Pt layer thickness depe ndence for the Ar sputtering case as x was varied from 5 angstrom to 2 0 angstrom, although the ohmic resistivity-rho(R) and the saturation m agnetization exhibit similar behavior. The estimated values for rho(H) , rho(R), Hall conductivity-gamma(HS) and extra-ordinary Hall coeffici ent R1 for a hypothetical "multilayer" Co film (x = 0) are all larger than those for "pure" sputtered Co films. Moreover, it was not possibl e to explain the observed variation of rho(H) with the Pt layer thickn ess with the short-circuiting effect from the non-magnetic Pt layers a s predicted by a simple two-layer model. We suggest that the smaller-r ho(H) for the Xe sputtered Pt/Co films compared to Ar sputtered films can be attributed to reduced scattering suggesting a beneficial influe nce of the interface sharpness on the anisotropy of Pt/Co multilayers.