Fabrication and properties of transparentmagneto-optical ceramics

Transparent Tb2Ti2O7 magneto-optical ceramics were fabricated from co-precipitated nano-powders by vacuum pre-sintering with hot isostatic pressing (HIP) post-treatment. The formation of pyrochlore phase, decomposition of the precursor, and the morphology of powders calcined at different temperatures were investigated. The inline transmittance of Tb2Ti2O7 ceramics, which were pre-sintered at 1350 degrees C for 2 h with HIP post-treatment at 1450 degrees C for 3 h and subsequently annealed at 800 degrees C for 20 h in NH3 atmosphere, reaches 65.5 % at 1064 nm. The Verdet constant of Tb2Ti2O7 ceramics is -229.0 +/- 0.6 rad center dot T-1 m-1 at the wavelength of 633 nm, which is 71 % higher than that of the commercial Tb3Ga5O12 crystals. Tb2Ti2O7 magneto-optical ceramics show a promising application for Faraday rotators.