Abstract

Recently, the Roess-Lin scheme for the generation of picosecond dye laser pulses has been demonstrated in cascade.¹ This cascade-pumped dye laser (CDL) was shown to produce dye laser pulses of 10-ps duration starting with 350-ps nitrogen laser pump pulses. The bandwidth was also measured to be ≳ 100 Å. For the CDL system to be more useful, the pulse duration stability has to be characterized and the bandwidth has to be narrowed. Because of the nature of the Roess-Lin scheme, intensity variations in the pump pulse translate into fluctuations in the duration of the output pulse. We have completely redesigned the CDL laser by replacing the first stage with a side-pumped dye laser. The thickness of the second stage was also decreased to produce a shorter cavity lifetime and wider mode spacing. By using a spectrometer to pass only one longitudinal mode, it was found that the bandwidth was 0.5 Å. Using a 2-ps streak camera to monitor 100 laser pulses, it was found that the average duration was 7.6 ps with a standard deviation of 0.7 ps. These near transform-limited ultrashort pulses can be amplified to high energy for further pulse compression or for performing nonlinear optics experiments.

© 1985 Optical Society of America