Fabrication and performance optimization of novel (Tb0.9975R0.0025)3Sc2Al3O12 (R= Pr, Ho, Dy, Eu) magneto-optical transparent ceramics.

Magneto-optical materials with high Verdet constants at high extinction ratios are desirable for the Faraday isolators. However, current terbium-based crystals have encountered several issues, such as low Verdet constants (TGG crystals), difficult growth (TSAG crystals), and low utilization of raw materials, which limit the development of the Faraday isolators. Here, R 0.0025 TSAG (R= Pr, Ho, Dy, Eu) transparent ceramics are prepared. The ceramics exhibit high optical transparency above 74.0% in the 525–1565 nm range and a high relative density of 98.9%. In particular, the transmittance of R 0.0025 TSAG ceramics at 1064 nm is approximately 81.6%, 81.6%, 79.8%, and 80.6%, respectively. The Verdet constants of R 0.0025 TSAG ceramics at the measurement wavelength are greater than those of the TSAG ceramic. The compelling magneto-optical performance of the Dy 0.0025 TSAG ceramic includes a high Verdet constant of 161.8 ± 3 rad·m−1·T−1 at 635 nm. The Verdet constant of the Dy 0.0025 TSAG ceramic is still superior to that of TSAG ceramic in the same temperature range. The extinction ratios of the R 0.0025 TSAG (R= Pr, Ho, Dy) ceramics exceed 40 dB. The figure of merit points out the superior characteristics of R 0.0025 TSAG ceramics. Moreover, R 0.0025 TSAG (R= Pr, Ho, Dy) ceramics with a thickness above the centimeter level are successfully prepared. This work indicates that the Dy 0.0025 TSAG ceramic can promote the miniaturization of magneto-optical isolators and can be applied in high-power lasers. • (Tb 0.9975 R 0.0025) 3 Sc 2 Al 3 O 12 (R= Pr, Ho, Dy, Eu) transparent ceramics were synthesized and characterized. • The Verdet constants of R-TSAG ceramics at the measurement wavelength are greater than that of TSAG ceramic. • The values of extinction ratio for R-TSAG (R= Pr, Ho, Dy) ceramics exceed 40 dB. [ABSTRACT FROM AUTHOR]