Optically biased tunable femtosecond dye laser and spectral windowing of the compressed second harmonic of Nd: YAG.

We describe a technique for enhancing tunable ultrashort pulse pumped dye laser performance based on the use of "long" pump pulses to optically bias the cavity toward minimal losses. Increases in dye laser output power of 155% and powers as high as 125 mW have been measured with pulse durations under 300 fsec. Optical pulses as short as 180 fsec are reported for this ultrashort pulse pumped dye laser oscillator. We also report the first measurements of the spectral windowing of compressed 532-nm pulses for temporal pulse shaping, in the optimal group velocity dispersion limit. Temporal pulse shaping is demonstrated with small losses in power and minimal pulse broadening.