NEW PHOTOPOLYMERS BASED ON TWO-PHOTON ABSORBING CHROMOPHORES AND APPLICATION TO THREE-DIMENSIONAL MICROFABRICATION AND OPTICAL STORAGE

摘要

Molecules exhibiting strong two-photon absorption hold great potential for a wide range of applications including two-photon fluorescence imaging, three-dimensional (3D) optical data storage, and 3D microfabrication. We have observed two-photon absorptivities as high as 1500 × 10~(-50) cm~4 s/photon in bis-donor diphenylpolyene derivatives that are correlated to simultaneous charge transfer from the end groups to the polyene bridge in the molecule. Many of these molecules are also excellent photoexcitable electron donors that can initiate charge-transfer reactions with acrylate monomers. Marcus theory is used to describe the efficiency of these charge-transfer reactions. Polymerization rates have also been measured and we show that these two-photon chromophores display increased sensitivity and recording speed over conventional UV photo-initiators. The fabrication of complex, three-dimensional structures by two-photon polymerization is demonstrated and discussed in the context of advanced photonic applications.