Research On Polarization Holography And Photoinduced Birefringence Of Azo Film Doped With Gold Nanoparticles

Azo-organic compounds have been used as traditional dye materials in many industries such as textile,clothing and chemistry since they were invented in 1836.In addition,the azo dyes also have a place in the fields of photoelectric materials and optical functional devices due to their unique characters of photoisomerization and photoinduced anisotropy.There is no doubt that improving the photoinduced anisotropy of azo molecules is of great significance to broaden the utilization space further of azo organic materials.Metal nanoparticles have the effect of surface plasma resonance(SPR)which results in the local electromagnetic enhancement and has been applied in detection of biological and chemical molecules,spectrum technology.The optical properties of azo molecules can be improved by introducing metal nanoparticles.Besides this,the surface enhanced Raman spectroscopy is an important application of metal surface effect,which is helpful to study the adsorption behavior of azo molecule on metal surface.In this paper,we studied the photoinduced anisotropy of two azo films based on the metal surface plasmon resonance and the local field enhancement effect.One of the two films was doped with Au nanoparticles.The diffraction efficiency of polarization holographic gratings and polarization induced birefringence were compared.As the application of SPR of metal nanoparticles,we also studied the surface enhanced Raman spectra of azobenzene molecules based on silver colloidal sol substrate.The surface adsorption state was obtained,which may be helpful for the study of interaction between metal nanoparticle and azo molecule.