Functionalization of heterocyclic diphenylamino-based two-photon absorbing materials for microfabrication, data storage and upconverted imaging

Two-photon absorption (TPA), a molecular excitation process by the simultaneous absorption of two photons, has recently attracted growing interest in many photonic and optical applications because of the availability of chromophores that exhibit large, effective TPA cross-sections. Over the past 6-7 years, we have successfully synthesized a family of TPA molecules (designated as AFX) that possess large nonlinear optical properties, including unsymmetrical and multi-branched chromophores comprised of 'electron acceptor-aromatic bridge-electron donor' structural motif. These chromophores are excitable with useful wavelengths around 800 nm and fluoresce in the 400-450 nm region. However, practical uses of these chromophores depend on developing functionalization chemistry pertinent to specific applications. We are particularly interested in incorporating these TPA active molecules into polymeric or low melting glassy materials that are amenable to easy processing and fabrication. Our recent results in this direction will be discussed in this paper.