Diode‐Pumped Yb:YAG Ceramic Laser

Transparent polycrystalline Yb:YAG ceramics were fabricated by solid‐state reactive sintering a mixture of commercial Al 2 O 3 , Y 2 O 3 , and Yb 2 O 3 powders. The powders were mixed in ethanol and doped with 0.5 wt% tetraethoxysilane, dried, and pressed. Pressed samples were sintered at 1730°C in vacuum. Transparent fully dense samples with grain sizes of several micrometers were obtained. The phase from 1500° to 1700°C was important for the grain growth, in which the grains grew quickly and a mass of pores were eliminated from the body of the sample. Annealing was an important step to remove the vacancies of oxygen and transform Yb 2+ to Yb 3+ . The 1 at.% Yb:YAG ceramic sample was pumped by a diode laser to study the laser properties. The maximum output power of 1.02 W was obtained with a slope efficiency of 25% at 1030 nm. The size of the lasering sample was 4 mm × 4 mm × 3 mm.