An all-optical picosecond switch in polydiacetylene

Abstract

A polydiacetylene derivative of 2-methyl-4-nitroaniline (PDAMNA) showed a picosecond switching property. This phenomenon was demonstrated by waveguiding a cw He–Ne laser collinearly with a mode-locked picosecond Nd:YAG laser at 532 nm through a hollow fiber coated on the inside with a thin film of PDAMNA. The Z-scan investigations of PDAMNA thin films revealed that the PDAMNA system is a three-level system and the switching is caused by excited state absorption of the He–Ne beam.