Investigation of Third Order Nonlinear Optical Properties in S-Indacene-1,3,5,7(2h,6h)-tetraone Based D-π-A-π-D Chromophores by Z-Scan

Here we describe the synthesis and characterization of a series of centro-symmetric D-π-A-π-D chromophores based on an s-indacene-1,3,5,7(2H,6H)-tetraone acceptor with conjugated linkers containing thiophene and pyrrole moieties. These materials were studied by UV visible absorption spectroscopy and their third order nonlinear optical properties investigated by z-scan at 1064 nm. The introduction of conjugated pyrrole linkers was found to give an effective third order hyperpolarizability of -1.54 x10-30 esu, and an effective two photon absorption cross section of 6100 GM at 1064 nm. As these chromophores showed comparatively high effective nonlinear absorption they have potential in photonic applications such as optical limiting, optical communication, and for two photon initiated polymerization.