<title>Magnetization-induced second-harmonic generation imaging of buried magnetic interfaces</title>

Abstract

ABSTRACT Magnetization-induced second harmonic generation is selectively sensitive to the magnetization of surfaces or buriedinterfaces. We have used it to obtain images covering areas up to 100 .tm wide ofthe magnetic domain structures of Fe/Pdand Co/Pt buried interfaces with a micrometer resolution.Keywords: Optical materials, magnetic interfaces, SHG microscopy, optical storage In nanostructures for optical storage, in which at least one of the dimensions is of the order of a few atoms, interface properties can become dominant as compared to bulk properties. In this framework, nonlinear optical techniques offertheunique advantage of allowing a selective probing of surfaces or buried interfaces. In media without inversion symmetry,second harmonic generation is only allowed at interfaces, where the symmetry is broken. In the case of magnetic interfaces,the nonlinear Magnetization-induced Second Harmonic Generation (MSHG, also called NOMOKE for NOnlinear Magneto-Optical Kerr Effect)derives its specific interface magnetization sensitivity from the magnetization (M) dependent secondorder x(2)(± M) tensor {l]. Using both MSHG and the linear MOKE effect, differencesbetween the bulk and interfacemagnetic properties of cobalt-based multilayers have been observed [2]. In order to explain such results, it is essential toobtain images of the internal magnetic