An improved method for separating the kinetics of anisotropic and topographic gratings in side-chain azobenzene polyesters

The induction of anisotropy gratings in side-chain azobenzene polyesters is accompanied by the formation of surface relief. We introduce an improved h olographic method to separate the contributions of the anisotropic and the topographic part to the diffraction efficiency by analyzing the polarizatio n of the first-order diffracted beam. The main advantage of this method is that both parts can be determined simultaneously by only one measurement. F urthermore the displacement between both gratings can be determined in a si milar manner. Experimental results obtained with two different polyesters a re presented.