High-repetition tunable picosecond dye laser pumped by a copper bromide laser

It is reported that by mixing the saturable absorber DODCI with the gain medium Rh6G, 30-ps pulses can be generated from a short-cavity dye laser pumped by a copper bromide laser with a 25-ns pulsewidth and a 10-kHz repetition rate. A theoretical analysis of pulse shortening by this method is shown to agree with experimental results. A dispersion-amplifier system was employed for synchronous amplification and frequency tuning of the dye laser. The single-pulse energy was up to 0.15 mu J with a linewidth-of 1.0 cm/sup -1/ in a one-stage amplifier, and the amplified spontaneous emission (ASE) background noise was reduced to below 10%. By simply rotating the grating and occasionally adjusting the thickness of the dye cavity slightly, the laser can be tuned continuously from 570 to 590 nm with a nearly Fourier-transform-limited linewidth. The repetition rate can be varied from 10 to 20 kHz.<
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