Fabrication of the Second-Order NLO Self-Assembled Films with High Thermal Stability

The non-linear optical films were fabricated by means of alternate electrostatic adsorption with positively charged diazoresin (DR) or with negatively charged azo polymer (PAZO).Regular films growth during adsorption was proved by means of UV-vis spectroscopy.Upon the UV irradiation,accompanied with the transition of the ionic bonds between the layers to covalent bonds,the resulting multilayer films possess excellent environmental stability and high thermal stability.Optical second-harmonic generation (SHG) was observed in the multilayer films.