Crystallization and dielectric and optical properties of borate glasses (1-x)Na2B4O7+xNb2O5

The crystallization and dielectric and optical properties of glasses (1 - x)Na2B4O7 + xNb(2)O(5), where x = 0.15-0.35, have been studied. The formation of structural entities based on NbO6 octahedra in the glass has been detected by Raman spectroscopy. In the thermally poled glass, a layer with nonlinear optical properties is formed under the anode surface. The nonlinear optical properties of the poled sample have been studied by the second harmonic generation method using laser radiation. The nonlinear optical coefficient d (33) for the poled glass with the maximal content of niobia is 0.1 pm/V.