Effect of charge carrier blocking, surface resistance and electric field distribution on electric field poling of nonlinear optic polymers

In our previous work we introduced charge carrier blocking layers to realize an increase in the poling field and, hence, an increase in the nonlinearity, or electro-optic (EO) coefficient, r(33), of the nonlinear optic (NLO) polymer disperse red 1: polymethylmethacrylate (DR1: PMMA). In addition, we not only achieved higher poling voltages, which resulted in higher r(33)s at these higher poling voltages, but we also observed higher r(33)s when both the samples with and without the charge carrier blocking layers were poled at the same poling voltage. We attributed that primarily to a decrease in the surface resistance. Here we provide a more detailed analysis and propose that the increase may be attributed not only to surface resistance but a combination of lower surface resistance, more uniform electric field distribution and charge carrier blocking, provided by the charge carrier blocking layers.