Tb ₃ Al _2.5 Ga _2.5 O ₁₂ transparent ceramic for magneto‐optical application

Abstract The optical quality and microstructure of the Tb ₃ Al _2.5 Ga _2.5 O ₁₂ transparent ceramic were investigated and compared with those of terbium gallium garnet (Tb ₃ Ga ₅ O ₁₂ TGG ) and terbium aluminum garnet (Tb ₃ Al ₅ O ₁₂ TAG). The transmission of the Tb ₃ Al _2.5 Ga _2.5 O ₁₂ ceramic was as high as 80% in the visible and near‐infrared ( IR ) regions, which was close to the theoretical value. The Verdet constant of the Tb ₃ Al _2.5 Ga _2.5 O ₁₂ ceramic measured at 632.8 nm and room temperature was −150.6 rad/Tm, which was 12% larger than that of the TGG single crystal and 13% smaller than that of the TAG single crystal, and the Tb ₃ Al _2.5 Ga _2.5 O ₁₂ ceramic showed the highest transparency among these three samples.