Field-responsive materials conjugated polymers

The relation between the EA response and the macroscopic nonlinear properties of the material has been drawn by a classical approach. In Section 19.3.3, the mechanism behind the field-induced variation will be explored by a quantum mechanical approach. In molecular solids and in conjugated polymers, where the states are localized to a high degree, the change in a with the electric field is in general ascribed to a Stark shift of the molecular energy levels. 

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