Third-order nonlinear optical properties of new polyfluoroalkylsulfanyl-substituted tetrathiafulvalene derivatives

We investigate the third-order nonlinearities of new polyfluoroalkylsulfanyl-substituted tetrathiafulvalene derivatives using the degenerate four wave mixing method (DFWM). For each compound, the study of the influence of the concentration on DFWM efficiency leads to the choice of an optimum solution for which DFWM efficiency R attains its maximum. From the measurements of R versus the pump intensity, we deduce the values of third-order susceptibilities χ〈3〉 and the corresponding second-order hyperpolarizabilities γ. The largest γ obtained is 103 larger than the γ value of CS2.