2ND-HARMONIC GENERATION OF ELECTRICALLY POLED BOROPHOSPHATE GLASSES -EFFECTS OF INTRODUCING NIOBIUM OR SODIUM OXIDES

Second-harmonic generation in poled glasses opens new frontiers in opt ical material research. Within this context new borophosphate glasses of the Ca(PO3)(2)-CaB4O7-Na2B4O7-Nb2O5 system were synthesized and the ir second-harmonic generation was evaluated after poling treatment. Th e enhancement of the second-harmonic signal with niobium oxide content is related to the presence of distorted NbO6 octahedra in the former of the glasses and to the increase in third-order susceptibility, The intensity of the measured second-harmonic signal is not dependent on t he amount of sodium (100-1000 ppm) introduced into the glass. (C) 1997 Academic Press.