Intracavity difference-frequency generation of near-infrared picosecond pulses in a synchronously mode-locked cw dye laser

Intracavity downconversion is demonstrated in a Coumarin 30 dye laser synchronously pumped by the second harmonic of a mode-locked Ti:sapphire laser. Infrared pulses of 1.6-ps duration at milliwatt average powers are generated by difference-frequency mixing in a KTiOPO(4) crystal with injected pulses at the fundamental of the pump laser. Tunability of more than 500 nm, centered at 1550 nm, is achieved with a single dye and a single crystal by use of a single set of optics.