Optically Tunable Nonlinearities in Polymers Based on Photoisomerizable Metal-Based Coordination Complexes

The bottom‐up design of polymer films exhibiting quadratic nonlinear optical properties that can be tuned optically and chemically is described. The polymer matrices are doped with metal‐containing chromophores built around a ZnII core and photoisomerizable ligands with two different geometries. These molecules possess specifically designed photophysical and nonlinear optical properties to be used towards all‐optical poling, an interference process between one‐ and two‐photon excitations that locally induces macroscopic second‐order effects in polymer films. It is shown that grafting the molecules onto the polymer chains improves the stability of the macroscopic photoinduced nonlinearity in the films. The bottom‐up design of polymer films exhibiting quadratic nonlinear optical properties is described. Chromophores built around a ZnII core and photoisomerizable ligands are optically poled (see figure). The photoinduced nonlinear optical response is optimized by tuning the molecular symmetry, orientation conditions, and by grafting the molecules on the polymer chains. Applications to photonics engineering are discussed.