Ellipsometric Selective Sensitivity to Magnetic Nanostructures

Recently, we have shown that the approach of depth sensitivity of magneto-optic ellipsometry can be generalized to selectivity from different materials in nanostructures. We use the condition number as the figure of merit to quantify the magneto-optic selectivity to two different magnetic contributions in magnetic nanostructure. The method is demonstrated on nanostructures containing magnetically hard Fe particles in surface layer of soft FeNbB amorphous ribbon. We separated both magnetic contributions from measurement of hysteresis loops using magneto-optic Kerr effect in longitudinal configuration. Magneto-optic selectivity is discussed and theoretical model on the basis of effective medium is compared with experimental data of longitudinal magneto-optic Kerr effect depending on angle of incidence.