INTENSITY SCAN AND 2-PHOTON ABSORPTION AND NONLINEAR REFRACTION OF C-60 IN TOLUENE

A single beam technique is introduced to determine the magnitude and s ign of third order nonlinear optical coefficients of materials using i ntensity dependence of the complex refractive index, It is applicable to a large range of materials including those with a low damage thresh old such as polymers and absorbing glasses, It is used to determine th e two photon absorption and nonlinear refraction coefficients of C-60 in toluene. Concentration dependence of the nonlinear optical coeffici ents results in second hyperpolarizabilities of 10(-31) (esu) for C-60 . (C) 1996 American Institute of Physics.