Optical Property Influence on Magneto-optics of CoNi and TbCo Multilayers on Noble Metal Alloy Substrates*

Spectroscopic (300-800 nm) magneto-optic measurements (polar Kerr rotation and ellipticity), as well as spectroscopic (250-1000 nm) ellipsometric measurements have been taken on a series of CoNi and TbCo multilayer nano-structures. The magnetic layers were sputter deposited onto AuxAg1-x alloy buffer layers (a range of x values were used) which were sputtered onto glass substrates. An interesting maxima in the Kerr rotation, appearing in the mid-visible region, shifts toward the blue with decreasing x values. A full electromagnetic analysis of this multilayer boundary value problem, including dielectric function representation for all constituent layers permits an understanding of the spectral data, and allows prediction of interesting new observable optic and magneto-optic phenomena.