Signal damping of second-harmonic generation in poled soda-lime silicate glass

We report second-harmonic generation in poled microscope slides of soda-lime silicate glass. During poling a sodium precipitate appears on the glass surface on the cathode side. Evidence of sodium motion through the sample helps us to understand the inducing mechanism of the second-order nonlinearity in the poled glass. We found decay of the second-harmonic signal over time. The decay rate increases with the ambient temperature, while the residual signal depends on the poling temperature.