Writing of Nonlinear Optical Single Crystal-Lines in Glass by Scanning YAG Laser Irradiation

Abstract

New technique for the writing of crystal-lines in glass by irradiations of a continuous Nd:YAG at a wavelength of 1064 nm, selective atom heat processing, which has been proposed by the present authors′ group, is applied to some glasses containing rare-earth (Sm³⁺, Dy³⁺) ions. It is found that this technique is effective in the writing of crystal-lines in TeO₂-, Bi₂O₃- and B₂O₃-based glasses. In the case of rare-earth doped BaO-B₂O₃ glasses, nonlinear optical β-BaB₂O₄ (BBO) crystal-lines with a width of ~ 5μm are fabricated. The crystal-lines show uniform second-harmonic generation (SHG). The rotation angle dependence of the sample against the incident laser on SHG in the crystal-lines is the same as that in commercially available y-cut β-BBO bulk single crystals, demonstrating that the crystal-lines written by YAG laser irradiations are β-BBO single crystals with the c-axis orientation along the laser scanning direction.