Does the contribution of PO4 group is exclusively responsible for the quadratic electrooptic effect in KDP-type crystals? Original Research Article

Measurements of temperature dependencies of the effective quadratic electrooptic coefficients View the MathML sourceno3|g1111-g2211| and View the MathML source|no3g1111-ne3g3311| in deuterated KDP are presented. The effective coefficients are found to decrease in a different way with temperature. This is explained in terms of different contributions of hydrogen bonds to the individual coefficients g1111, g2211, and g3311. The results obtained indicate that for optical phenomena related to the third-order susceptibility descriptions based only on contributions of PO4 tetrahedra are not precise enough.