Abstract

Polyaniline (PANI) is one of the most studied π-conjugated polymers for photonic applications. Most of the research on PANI has been concentrated on the undoped partially oxidized form, the emeraldine base (EB), and its protonated analog, the emeraldine salt (ES). So far, not much attention has been paid to the capabilities of the undoped fully reduced form of PANI, the leucoemeraldine base (LEB), as a nonlinear optical material. This investigation can also clarify, for example, how defects, such as those present in the EB form, modifies the nonlinear optical properties of the polymer. To achieve a better understanding, we performed our investigation at 532 nm. At this wavelength, the excitation is quasi-resonant with respect to the absorption band corresponding to defects (excitons) in the EB form of PANI.

© 2001 EPS