Fabrication and spectral properties of Yb,Ho:Y2O3 transparent ceramics

Yb,Ho:Y2O3 ceramics have been fabricated by Spark Plasma Sintering method (SPS). The microstructure and transmittance of the ceramics sintered from 1623 K to 1673 K were analyzed. The highest in-line transmittance of Yb,Ho:Y2O3 ceramic sintered at 1673 K reached almost 83% at 750 nm with the thickness of 1 mm. The absorption spectra, fluorescence spectra and fluorescence decay curve were recorded at room temperature. The Judd-Ofelt parameters Ω2, Ω4 and Ω6 were calculated to be 8.33 × 10−20 cm2, 1.81 × 10−20 cm2, and 0.82 × 10−20 cm2, respectively. The intense emission cross section of Yb,Ho:Y2O3 ceramic was 3.43 × 10−20 cm2 at 2057 nm with full width at half maximum (FWHM) of 208 nm. The results indicate that Yb,Ho:Y2O3 transparent ceramic can be a promising laser gain medium for laser operation around 2 μm.