In recent years there have been reports of large magneto-optic Kerr effects (MOKE) observed in structures consisting of thin magnetic layers on top of optically thick nonmagnetic reflecting materials. Feil and Haas introduced the concept that these large MOKE could be explained in terms of metallic plasma resonances.[l] Katayama et al found enhanced MOKE in Fe/Cu bilayers at wavelengths corresponding to the plasma edge of copper . Schoenes and Reim discussed the Feil and Haas work , and Reim and Weller demonstrated enhanced MOKE in TbFeCo/Cu at wavelengths where the optical constants n and k are small . Thus it appears that enhanced MOKE can result when materials have unusual optical dielectric functions.