Pulse shortening in dye laser side-pumped by TEA N2laser

The temporal behavior of the output from a homemade TEA-N2-laser (750 ps pulsewidth) pumped dye (R6G) laser was observed with the aid of a streak camera. The observed output pulsewidths are between 60 and 160 ps depending on the configuration of the dye laser cavity. The shortest (50 ps) pulse is obtained when the distances between output mirror and dye cell, and dye cell and grating, are 10 and 105 mm, respectively. The mechanism of the short pulse generation is clarified by comparing experimental results with the results obtained by solving rate equations numerically, where the position dependences of excited-state population and photon flux were taken into account.