Photophysics of the all-optical orientation dynamics of a pyrylium salt

The all-optical poling of polymers is a key process for the optical control of plastic materials for second order nonlinear optical effects. It is based on the photochromic behavior of dyes submitted to bi-color exciting laser beams. In order to achieve a total control of the process, active research is performed in the search for efficient transparent materials and efficient opto-mechanical coupling mechanisms of photochromic dye molecules in polymer matrices. We hereby propose and demonstrate the use of twisted internal charge transfer (TICT) for the all-optical poling of tri-aryl-pyrylium cations.