Fabrication and optical properties of garnet ceramics based on Y 3- x Sc x Al 5 O 12 doped with ytterbium and erbium.

Optical ceramics YSAG:Yb,Er with an average grain size of 6 ± 1 microns were fabricated by vacuum sintering of nanocrystalline powders of the compositions Y 2.34 Yb 0.45 Er 0.09 Sc 0.20 Al 4.92 O 12 , Y 1.66 Yb 0.45 Er 0.09 Sc 1.00 Al 4.80 O 12 and Y 0.96 Yb 0.45 Er 0.09 Sc 1.70 Al 4.80 O 12 . The linear transmittance coefficients of the YSAG:Yb,Er ceramic samples exceed 80% in the visible and infrared regions. The refractive index of ceramics increased from 1.827 to 1.859 with an increase in scandium content. The effect of scandium cations at the dodecahedral site of the YSAG crystal lattice on the optical and luminescence characteristics of Yb 3+ ( 2 F 7/2 and 2 F 5/2 ) and Er 3+ ( 4 I 15/2 , 4 I 13/2 , 4 F 9/2 and 4 S 13/2 ) in wavelength ranges of 530-690 nm, 890-1080 nm, and 1430-1680 nm was revealed.