Time and temperature dependence of surface relief grating formation in polymers containing azobenzene groups with different dipole moment Available to Purchase

We present the results of time and temperature dependent deformation of two azobenzene materials with different dipole moment during the process of surface relief grating formation. The effect of chromophore orientation on grating formation in these films was studied in situ using continuous and pulselike exposure techniques at various temperatures up to the glass transition temperature of the respective polymer material. The results obtained for high dipole moment pDR1M and low dipole moment pMEA were compared in terms of the rate of the grating formation and related to the quantities as relaxation of the chromophores in the absence of the inscribing light and induced stress due to the chromophore orientation. The parameters obtained from the simulation data can be well explained considering viscoelastic material model. The experimental findings can be explained by assuming the interaction of azochromophores with polarized light leading to the orientation anisotropy of the azobenzene macromolecules, thereby generating a mechanical stress.