Distribution and amplification of an electric field in ferroelectric-dye heterostructures

The distribution of an electric field has been investigated in Langmuir-Blodgett thin-film heterostructures prepared by sequentially transferring layers of the ferroelectric copolymer poly(vinylidene fluoride-trifluoroethylene) P(70% VDF 70% –30% TrFE) and the azo dye. An alternating-current voltage applied to the electrodes is unevenly distributed across layers of the dye and the copolymer in accordance with a constant induction along the normal to the heterostructure. The electric-field-induced shift of the absorption spectrum of the dye serves as a probe of the electric field and reveals a noticeable amplification of the electric field in the dye layers (by a factor of 2–7). The electric field in the ferroelectric is directed opposite to the direction of the electric field applied to the electrodes of the heterostructure.