Fabrication and properties of 10 at.% Yb:Y₃Sc_1.5Al_3.5O₁₂ transparent ceramics

10 at.% Yb:Y₃Sc_1.5Al_3.5O₁₂ (Yb:YSAG) transparent ceramics were fabricated by the solid state reactive of high-purity Y₂O₃, α-Al₂O₃, Yb₂O₃ and Sc₂O₃ powders, utilizing MgO and tetraethoxysilane (TEOS) as the sintering aids. The Yb:YSAG ceramic sample sintered at 1820 °C for 10 h has a dense and homogenous microstructure with average grain size of 26.9 μm, whose in-line transmittance reaches 83.2% at 1100 nm (2 mm thick). The absorption and emission cross sections are calculated to be 5.09 × 10⁻²¹ cm² at 941 nm and 12.33 × 10⁻²¹ cm² at 1031 nm, respectively. The full width at half maximum (FWHM) of the main emission peak centered at 1031 nm is 12.4 nm, which is about 1.3 times larger than that of the 10 at.% Yb:YAG ceramics. By using the three-mirror resonator, the Yb:YSAG ceramic laser output power of 1.67 W at 1031 nm and slope efficiency of 13.1% were obtained with an output coupler (OC) of T = 5%.