Thermally stable and large second-order nonlinearity in poled silica films doped with Disperse Red 1 in high concentration

Abstract

Solgel-processed silica films doped with the organic azo dye Disperse Red 1 (DR1) are prepared in a higher concentration than previously reported. Second-harmonic generation (SHG) from corona-poled films is measured with the Maker fringe technique with a Nd:YAG laser (1064 nm). The second-order nonlinear-optical coefficient is evaluated as d15 = 27 pm/V, d31 = 26 pm/V, and d33 = 120 pm/V, at a DR1 concentration of 2.2 × 1021/cm3. The nonlinearity is stable for at least 1000 h at 125 °C without any relaxation.