Modulation length dependence of magneto-optical Kerr effect in Fe/Cu multilayer films

A relation between modulation length and wavelength dependence of polar magneto-optical Kerr rotation θ
K
in Fe/Cu compositionally modulated multilayer films has been investigated. A new peak of θ
K
appears at about λ = 560nm, corresponding to the absorption edge of Cu metal, and becomes large with the increase of modulation length D. The θ
K
peak moves towards longer wavelength side with increasing thickness ratio of Fe/Cu. There are optimum values of Fe/Cu thickness ratio and modulation length for the enhancement of θ
K
.