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 h v=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 h v≃1.4 eV) but also in the UV region (centered at h v≃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.