ON THE QUADRATIC ELECTROOPTIC EFFECT IN KDP

A theoretical and experimental investigation of the quadratic electro- optic effect in KDP is presented. By means of electromagnetic theory a n eigenvector approach is employed to account for the quadratic electr o-optic effect and also to estimate the contribution of the linear ele ctro-optic effect to the quadratic response of the crystal. A simple m ethod of measuring the coefficient g1212 in uniaxial crystals is descr ibed. Its value was found to be nearly two orders of magnitude smaller than the value measured earlier; however, it is comparable with the c oefficient g1111 - g1122 reported recently.