Simple generation of tunable near-infrared picosecond dye-laser pulses using spectre-temporal selection

The spectral and temporal processes in broadband pulsed-laser emissions of near-infrared dyes generated from low-Q and short laser cavities have been investigated with a rate equation model extended to a multiwavelength analy sis. A very fast spectral evolution is proved, and this leads to the intrin sic presence of a single short pulse on the short-wavelength wing of the br oadband IR dye laser spectrum. From the results, the direct generation of picosecond (approximate to 90 ps ) infrared dye-laser pulses adjustable in the 700-850 nm spectral range is successfully demonstrated with spectre-temporal selection, in a compact and simple device, using: a nitrogen laser (337.1 nm, 8 ns) or a e-switched ru by laser (694.3 nm, 25 ns) as a pumping source.