Electric field poling technique

For the DRl-MMA 35/65, N = 1.4 10 molecules/cm and P - 0.8 10 It implies a mean orientation ratio equal to 0.3, which is comparable to what can be achieved using the dc electric field poling technique such as corona poling. 

Using an electric-field poling technique, efficient EO property with moderate absorption loss is attained. 

Chromophores must be thermally robust enough to withstand temperatures encountered in electric field poling and subsequent processing of chromophore/polymer materials. Chromophore decomposition temperatures can be assessed by techniques such as thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA and DSC measurements on neat chromophore samples in air will tend to yield decomposition temperatures lower than those for the same chromophores in hardened polymer lattices. Typically, to be useful for development of device quality materials, a chromophore must exhibit thermal stability of 250 °C or higher (with thermal stability defined as... 

Detailed information about the components of the second-order susceptibility y2)(-2w to, w) can be obtained from second harmonic measurements on well-defined samples such as single crystals or oriented thin films, the latter obtained by procedures such as the asymmetric Langmuir-Blodgett deposition technique or electric-field poling of NLO chromophore-doped polymers.31 In the case of single-crystal samples, the second harmonic is... 

However, organic polymers, being amorphous, do not show second-order NLO effects. In order to employ them in second-order NLO measurements a polar order is induced by an external means such as electric field poling process or the Langmuir-Blodgett (LB) technique. Poled polymers and the majority of the LB films possess Cocv symmetry. Therefore, the second-order optical susceptibility tensor for SHG has only three independent nonzero elements, namely, zS ZzM Under Klienman symmetry [9] conjecture... 

Fig. S3. High quality, biaxially stretched PVDF ferroelectric film can be electrically poled to a remanent polarization of over 9 fxCcm with the Bauer cyclic poling technique. The polarization versus electric field of a typical sample is shown.

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