Epitaxial Bi-Gd-Sc iron-garnet films for magnetophotonic applications

Novel magneto-optical epitaxial bismuth-substituted iron garnet films of composition (BiGd)3(FeSc)5O12 with large lattice parameter of 12.570 Å have been grown and investigated. Their composition was uniquely chosen to get necessary values of the magnetic and magneto-optical parameters crucial for magneto-optical applications. In particular, the fabricated films have the suppressed cubic magnetic anisotropy (down to 1.2 × 103 erg/cm3) and the large magnetic susceptibility (∼50), due to introducing Sc3+ ions; the diminished saturation magnetization (4πMS ∼ 750 Gs), caused by Gd3+ ions, and relatively large specific Faraday rotation (1.75°/μm, at 655 nm), due to Bi3+ ions. Therefore, the grown magnetic films have record values of the product of the magnetic susceptibility by the Faraday rotation that makes them extremely promising for applications, including magnetometers, magneto-optical visualizers, light modulators and nonreciprocal elements of the integrated optics.