A new ultra-violet magneto-optical spectroscopic instrument and its application to Co-based multilayers and thin films

A magneto-optic measurement system for the 1.4-6.8 eV photon energy range (/spl lambda/=182-886 nm) is realized. A new technique to calibrate the applied modulator in-situ, essential for accurate measurements over such a wide range of photon energies, is demonstrated. Measurements at Co/Pt multilayers with 3 /spl Aring/ Co layers and various Pt layer thicknesses indicate a peak for the polar Kerr rotation (/spl sim/-0.5/spl deg/) at about 5.1 eV, which is not present in CoPt/sub 3/ alloy film. This feature may be partly due to quantum well effects, but there is also a possibility for an optical interference effect. Furthermore, positive Kerr rotations up to about +0.4/spl deg/ were found at photon energies above 5.7 eV.