Nonlinear optical properties of several siloxane polymer Langmuir-Blodgett films

Abstract The Langmuir-Blodgett film formation and the nonlinear optical properties of three polysiloxane polymer materials have been investigated. All three compounds could be built-up as Z-type layers on a variety of substrates. Experiments on the linear electrooptic (Pockels') effect revealed a second-order nonlinear susceptibility χ (2) (− ω ; ω , 0) of 10.6 pmV −1 for one of the materials; the order of magnitude of this result was confirmed using second-harmonic generation. For multilayer films the second-harmonic intensity was found to increase with the thickness of the LB structure. However, a linear dependence upon film thickness was evident, rather than the expected quadratic variation.