YAG laser-induced β-BaB2O4 crystalline dot formation in Sm2O3–BaO–B2O3 glasses Original Research Article

A continuous-wave (CW) YAG laser (power: 0.75–0.9 J/s, irradiation time: 15 s–15 min) with a wavelength of 1064 nm is irradiated to 11.1Sm2O3·44.4BaO·44.4B2O3 glass, and the formation of β-BaB2O4 (β-BBO) crystalline dots with a diameter of 30–150 μm is confirmed from micro-Raman spectra. β-BBO crystals with around 200 μm length grow towards the interior of the glass. The incorporation of Sm3+ into β-BBO crystalline dots is suggested from micro-Raman and fluorescence spectra. The second harmonic generation is detected from the array (10×10=100 dots) of β-BBO crystalline dots, indicating that each crystalline dot formed by YAG laser irradiation is a nonlinear optical crystal. CW YAG laser irradiation to glass with Sm3+ ions is a nice technique for a spatially controlled crystal growth.