Growth, High Optical Transmittance, and Strong Magneto-Optical Properties at 1550 nm of Ce,Bi-Codoped Tb 3 Fe 5 O 12 Crystals

This paper focuses on the enhancing effect of doped Bi 3+ and Ce 3+ ions on the specific Faraday rotation angle of the terbium iron garnet (TIG) magneto-optical crystal. By means of structural design, a large-radius Ce 3+ is doped into the dodecahedron sites of the bismuth-doped terbium iron garnet (Bi:TIG) structure. The cell volume of the crystal is enlarged to accommodate higher content of Bi 3+ and Ce 3+ . Centimeter-sized, high-quality cerium- and bismuth-codoped terbium iron garnet (Ce,Bi:TIG) and Bi:TIG crystals were successfully grown by the top-seeded solution growth (TSSG) method using a lead-free Bi 2 O 3 –Fe 2 O 3 flux. Among these as-grown crystals, the transmittance of Ce 0.13 Bi 0.60 Tb 2.27 Fe 4.85 Ga 0.15 O 12 is 70.7% and the specific Faraday rotation angle is up to −800 deg cm –1 at 1550 nm. The Faraday rotation temperature coefficients (FTC) and the wavelength coefficients (FWC) of Ce 0.13 Bi 0.60 Tb 2.27 Fe 4.85 Ga 0.15 O 12 are −1.72 × 10 –3 K –1 and 1.40 × 10 –3 nm –1, respectively. Ce,Bi:TIG crystal is expected to be applied in magneto-optical isolators at 1550 nm.