Enhancement of Faraday Effect in Highly Ce-Substituted YIG Epitaxial Films by RF Sputtering

Abstract

Faraday rotation and ellipticity spectra were measured at photon energy hv=0.9–4.0 eV for films of Y2Ce1Fe5O12 and Y3Fe5O12 epitaxially grown by rf sputtering. The Ce substitution prominently enhances Faraday effect with paramagnetic dispersion relation not only in the IR region (centered at hv≃1.4 eV) but also in the UV region (centered at hv≃3.1 eV). The enhancements in the IR and UV regions are nearly equal in magnitude but opposite in sign. Thus the magneto-optical enhancement by Ce in garnet can be ascribed to two electronic transitions centered around 1.4 and 3.1 eV.