Space-selective precipitation of functional crystals in glass by using a high repetition rate femtosecond laser

Nonlinear optical crystals Sr2TiSi2O8 can be written arbitrarily in a stoichiometric SrO-TiO2-SiO2 glass by using a high repetition rate femtosecond laser. The pictogram shows the Raman spectra of the laser-induced crystals (curve A) and the unirradiated glass (curve B). The inset shows the cross-polarized microscope images of the measured spot positions. The input power for inducing Sr2TiSi2O8 crystals was 850 mW.