YAG laser-induced structural modification in transition metal ion containing 40K2O–40Nb2O5–20SiO2 glasses

Glasses with the compositions of 40K2O–40Nb2O5–20SiO2 (in mol%) containing different concentrations (0.01, 1 and 2 mol%) of NiO were prepared by a melt quenching technique. The glasses were irradiated with a continuous wave Nd:YAG laser with a wavelength of 1064 nm, and a metastable crystalline phase of KNbO3 was obtained. In 2 mol% NiO-doped glass, lines with a width of ∼10 μm are successfully patterned by laser irradiations with a power of 0.9 W and a scanning speed of 15 μm/s. It is found from micro-Raman scattering spectra that the lines are composed of the metastable crystalline phase of KNbO3. The crystallization mechanism in Nd:YAG laser-induced crystallization in the glasses is discussed in comparison with the usual crystallization in an electric furnace.