Peculiarities of optical limiting effect in pi-conjugated organic systems based on 2-cyclooctylamino-5-nitropyridine doped with C-70

The optical limiting effect in 2-cyclooctylamino-5-nitropyridine (COANP) do ped with fullerenes has been investigated. The absorption saturation was fo und to be-in at the incident energy density of 4 J cm(-2). Optical limiting mechanisms have been specified in the fullerene-doped COANP compounds. The laser-induced refractive index and its influence on the optical limiting e ffect over the visible spectral range under nanosecond pulsed laser irradia tion have been studied. Using the dynamic holographic technique, nonlinear coefficients n(2) and chi ((3)) in C-70-doped COANP have been first determi ned.