Inkjet Printing of Yb:YAG Transparent Ceramic Planar Waveguide Laser Gain Medium

Herein, a YAG/10 at% Yb:YAG/YAG transparent ceramic planar waveguide (PWG) gain medium has been molded via inkjet printing and dry pressing molding. The composition and rheological property of ink are optimized along with the printing process to enhance the printing accuracy and quality. The PWG has dimensions of 13.5 × 8.0 × 1.8 mm³, while the thickness of the core Yb:YAG layer is ≈190 μm. The in-line transmittance of the PWG reaches 81.7% at 1030 nm, and the average grain size is ≈2.3 μm. The diffusion characteristics of Yb ions across the interface between the cladding YAG layer and the core Yb:YAG layer are investigated by calculating the diffusion coefficient and the mean diffusion distance of ¹⁷²Yb ions. The Yb:YAG PWG oscillator, which is pumped from a single end by a 940 nm laser diode, produces continuous wave laser at a wavelength of 1030 nm and exhibits the highest power (3.8 W) and highest absorbed–output slope efficiency (64.6%).