The design, synthesis, and evaluation of chromophores for second-harmonic generation in a polymer waveguide

In order to develop nonlinear optical chromophores for frequency doubling applications, it is important to understand the magnitudes of the relevant chromophore properties that will be required. In this paper the use of organic polymers with attached optically nonlinear chromophores to form waveguide second-harmonic-generation devices will be discussed. In particular, the use of such a frequency doubling device in optical storage applications will be considered. To this end limits on the quantity μβ are obtained where μ is the dipole moment and β the hyperpolarizability. Experimental values for electron donor/acceptor-substituted benzenes, stilbenes, and tolanes are compared to these requirements. None of the chromophores treated here have both sufficiently high optical nonlinearity and sufficiently low optical absorption at a doubled optical frequency of 400 nm to be practical in the specific application described.