Magnetism and magnetooptical effects in Ce--Fe oxides

The magnetic and magnetooptical properties of CeFe[O.sub.3] (CFO) and YCeCoFe[O.sub.6] (YCFCO) films grown by pulsed laser deposition onto MgO or SrTi[O.sub.3](100) substrates at ~[10.sup.-5] Torr or at 6 mTorr [O.sub.2] are studied. Faraday rotation hysteresis loops were obtained at the 1.55-[micro]m wavelength, yielding a saturation of ~0.6 deg/[micro]m in all CFO films and ~0.25 deg/[micro]m in the YCFCO film grown under vacuum. Optical measurements give a refractive index of 2.9 and an optical absorption of 1.8 dB/[micro]m at the same wavelength. The corresponding saturation magnetization in CFO films reaches 45 emu/[cm.sup.3] at room temperature. Interpretation of the magnetic and magnetooptical properties is based on the electronic structure and optical transitions of [Ce.sup.3+] in an iron garnet or orthoferrite lattice. Index Terms--Laser ablation, magnetooptic films, optical isolators.