THERMALLY STABLE AND LARGE 2ND-ORDER NONLINEARITY IN POLED SILICA FILMS DOPED WITH DISPERSE-RED-1 IN HIGH-CONCENTRATION

Solgel-processed silica films doped with the organic azo dye Disperse Red 1 (DR1) are prepared in a higher concentration than previously rep orted. Second-harmonic generation (SHG) from corona-poled films is mea sured with the Maker fringe technique with a Nd:YAG laser (1064 nm). T he second-order nonlinear-optical coefficient is evaluated as d(15) = 27 pm/V, d(31) = 26 pm/V, and d(33) = 120 pm/V, at a DR1 concentration of 2.2 x 10(21)/cm(3). The nonlinearity is stable for at least 1000 h at 125 degrees C without any relaxation. (C) 1995 Optical Society of America