Measurement of the third order nonlinear properties of conjugated polymers embedded in porous silicon and silica
Résumé
Third order nonlinear properties of new composite materials obtained by embedding conjugate polymers in porous silicon and silica matrices are measured in near infrared. A new technique so-called "I-scan" was used as alternative to the classical z-scan, since better adapted to the particular form of samples. The picoseconds measurements show a significant increase of the nonlinear refractive index not only with respect to the standard optical materials but also to the bulk conjugated polymers. Embedding of PTS, PT12, and PPV in nanopores enhances considerably their already very large nonlinear refraction index and lower their overall absorption due to a negative nonlinear absorption.