Dimethylamino-4,-nitrostilbene polymer

Zhang, Q., M. Canva, and G. Stegeman. 1998. Wavelength dependence of 4-dimethylamino-4 -nitrostilbene polymer thin film photodegradation. Appl Phys Lett 73 912-914. 

Dopant orientation during and following electric field-induced poling can be studied continuously and in real time in order to examine the microenvironment surrounding the dopants in terms of the polymer relaxations and the applied corona field. In the results presented below, the SHG of 4-dimethylamino-4 -nitrostilbene (DANS) dispersed in polystyrene (PS) or poly(methyl methacrylate) (PMMA) matrices has been examined in corona poled films as a function of temperature in order to understand the effect of thermal conditions on the temporal stability of the dopant orientation. 

In this chapter, we present the fabrication parameters and optical performances of the packaged polymeric MZ waveguide modulator for photonic applications using a polymethyl methacrylate (PMMA-based side-chain polymer with 4-dimethylamino-4 -nitrostilbene (DANS). We discuss the design considerations for single-mode propagation at a wavelength of 1.3 fim in relation to the fabrication sequence. In particular, we discuss the optical power stability of our devices in detail. 

Second-order nonlinear optical properties require noncentrosymmetric structure. On the molecular level this is usually obtained by push-pull systems such as 4-7V,N-dimethylamino-4 -nitrostilbene (DANS) see Fig. 36a. But (/3> and subsequently will be zero if the macroscopic structure of the material is centrosym-metric. Therefore, polymers are usually poled to induce a noncentrosymmetric structure i.e., a high electric field is applied and the polar order is frozen in the glassy state. Problems are the relatively low polar order and its temporal and thermal instability. 

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