Nd:LuAG transparent ceramics fabricated by solid-state reactive sintering

For high repetition rate nanosecond high power solid-state lasers, it is essential to choose gain media with moderate saturation flux. Among these, Nd:LuAG transparent ceramics have shown significant potential due to their outstanding optical, mechanical, and thermodynamic properties. Garnet laser ceramics have the characteristics of high theoretical optical quality, short preparation cycle, high thermal conductivity, the ability to achieve high-concentration and uniform doping of active ions, and ease of fabricating composite structures. They are a promising gain medium material with great application potential. Using the commercial Lu₂O₃, α-Al₂O₃ and Nd₂O₃ powders as raw powders. The 1 at.% Nd:LuAG transparent ceramics with different TEOS additions were fabricated by vacuum pre-sintering at 1825 ℃ for 5 h and HIP post-treatment at 1750 ℃ for 3 h using TEOS and CaO as sintering additives. The average grain size of the 1 at.% Nd:LuAG transparent ceramic after HIP (1750 °C × 3 h, 200 MPa) is approximately 15.2 μm. The in-line transmittances at 1064 nm initially increases and then decreases with the increase in TEOS addition. The in-line transmittances of 1 at.% Nd:LuAG transparent ceramic with 0.6 wt.% TEOS and 0.05 wt.% CaO is 83.6% at 1064 nm. The successful preparation of high optical quality Nd:LuAG transparent ceramics is of great significance for the enhancement of the performance of repetitive frequency nanosecond high-energy solid-state lasers.