Second-Order Hyperpolarizabilities of Organic Ionic Species

Abstract

Abstract The second-order hyperpolarizabilities (β) of two categories of organic ionic species were evaluated by the hyper Rayleigh scattering method. The ⟨β⟩ of (dimethylamino)stilbazolium analogues in methanol with long cut-off wavelength more than 600 nm, which can be used for electro-optic modulation, were evaluated to be in the order of 10−27 esu using 1064 nm light as a fundamental beam. Aromatic sulfonates in the second category were found to have comparatively large |β| values irrespective of short cut-off wavelength: In the case of sodium p-toluenesulfonate with cut-off of 280 nm, |β| in methanol was 2.2×10−29 esu and was about two thirds of p-nitroaniline with cut-off of 445 nm.