Quadratic NLO Properties of Photopatterned Chromophore Doped Photocrosslinkable Materials
J.P. Bombenger, L. Mager, A. Fort and C. Carre
We present an organic photo-crosslinkable material where the quadratic NLO properties can be patterned. The material includes a triacrylic monomer, sensitized in the visible range by addition Irgacure 784 (Ciba speciality). The NLO chromophore is a nitrostilbene derivative functionalized by two crosslinkable acrylate functions. The photo-patterning of the NLO properties is achieved by spatially controlled photocrosslinking. We have demonstrated that the lifetime of the quadratic hyperpolarizability extends over several thousand hours at room temperature (RT). We study the evolution of the NLO properties. As the relaxation of the chromophore orientation extends over weeks at RT, we have developed a thermally induced relaxation experiment. Using a simple model, one obtains the relaxation at RT after a two hour measurement time.