Abstract

We have developed novel multifunctional chromophores as a new class of organic nonlinear optical molecules for photorefractive applications. Photoconductive property and second-order nonlinear optical response were characterized by xerographic discharge and second-harmonic generation measurements, respectively. Two kinds of molecular systems were studied: acceptor-substituted carbazoles and asymmetrically substituted metallophthalocyanines. Carbazoles and metallophthalocyanines are well known molecules which possess photoconductivities: hole-transporting and carrier generation properties. In order to add the second-order nonlinear optical properties at a molecular level, we introduced acceptor groups into these molecules. The asymmetrically substituted metallophthalocyanines and the carbazole oligomers: head-to-tail linear, cyclic and starburst oligomers, were newly designed as shown in Figure 1. The physical properties of carbazole oligomers are different from corresponding point-like molecules and their optoelectronic properties can be controlled by molecular-level-tuning of the size, shape, surface chemistry, and topology. The carbazole starburst oligomer films obtained by spin-coating were poled and exhibited second-order nonlinear optical responses.

© 1995 IEEE