Abstract

Random lasing and second harmonic generation after two-photon excitation was observed for the first time, in both scattering and amplifying polymer samples. Pumping was performed with sub-picosecond laser pulses at 830 nm and the emission, was observed with a spectrograph streak camera detection system for simultaneous recording of spectral and temporal features. SHG was detected at 415 nm and random lasing at 470 nm. The advantages of two photons absorption are discussed because of its enhanced detection efficiency and minimized effects on the irradiated sample (e.g. healthy tissue surrounding tumors).

© 2001 OSA/SPIE