Abstract

Organic compounds have been attracted much attention as nonlinear optical materials because these provide the large nonlinear susceptibility and the ultrafast response by the use of the electronic transition rather than inorganics. Although organic compounds possess a large susceptibility compared to the inorganics, nonlinear susceptibility from these reported so far was two or three orders of magnitude less than the criterion for a practical use. Thus the enhancement of optical nonlinearity for organic compounds is seriously expected to fulfill the future phtonic applications. One of the most interesting techniques to control and enhance the nonlinear optical properties of organic compounds is to exploit the optically pumped excited states.¹-⁴ In the present paper, one-dimensional conjugated polymer which exhibits a large optical nonlinearity in the ground state was used to investigate the optical pumping effect on the degenerate four wave mixing, third order nonlinear optical process. Femtosecond optical pumping of conjugated polymer could produce a significant enhancement of the third order nonlinearity.

© 1996 Optical Society of America