Intensity-Induced Changes in Optical Polarizations in Glasses

Using a single-mode ruby laser we have made the first measurements of intensity-induced changes of the optical polarization (ellipse rotation) in solids, viz., fused quartz and Schott BK-7 and SF-7 glasses for which we have obtained the nonlinear susceptibility values ${c}_{1221}(\ensuremath{-}\ensuremath{\omega}, \ensuremath{\omega}, \ensuremath{\omega}, \ensuremath{-}\ensuremath{\omega})=1.5, 2.3, \mathrm{and} 9.9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}15}$ esu, respectively. These values are accurate to within 10% relative to the value for liquid C${\mathrm{S}}_{2}$, which we used for calibration and determined from other experiments to be 37.8\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}14}$ esu to within 2%. We also show theoretically that a comparison of these values with electric-field-induced birefringence (Kerr) data can determine uniquely the fractional contribution to both of purely electronic nonlinearities. Existing Kerr data are only accurate enough at present for us to conclude that the electronic nonlinearities might dominate our effect.