Space-Selective Precipitation of Ba2TiSi2O8 Crystals in Sm3+-Doped BaO--TiO2--SiO2 Glass by Femtosecond Laser Irradiation
Space-Selective Precipitation of Ba2TiSi2O8 Crystals in Sm3^＋-Doped BaO-TiO2-SiO2 Glass by Femtosecond Laser Irradiation

The ferroelectric crystal Ba2TiSi2O8 with high second-order optical nonlinearityis precipitated in Sm3+-doped BaO--TiO2--SiO2 glass by a focused 800nm, 250kHz and 150fs femtosecond laser irradiation. No apparent blue and red emissions are observed at the beginning, while strong blue emission due to second harmonic generation and red emission due to the f--f transitions ofSm3+ are observed near the focal point of the laser beam after irradiation for 25s. Micro-Raman spectra confirm that Ba2TiSi2O8 crystalline dots and lines are formed after laser irradiation. The mechanism of the phenomenon is discussed.