Fabrication of transparent borate glasses containing β-BaB2O4 by incorporation method

The fabrication of transparent B2O3-based glasses containing non-linear optical crystal of β-BaB2O4 (BBO) particle by incorporation method was studied. The BBO particle with a diameter of about 10 μm has been successfully incorporated into BaO–B2O3–SiO2 glasses by adjusting the melting temperature, soaking time and the amount of BBO. The β-phase could be transformed to α-phase when the remelting time and/or temperature was increased. A small difference in the refractive index n, between matrix glasses and incorporated crystals, is a significant reason for the transparency. The refractive index of the remelted sample was independent of particle size, and was increased by adding more contents of BBO. Moreover, the best efficiency for second harmonic generation (SHG) was 2.5% of the BBO crystal.