Abstract

We describe a regeneratively mode-locked Tisapphire laser which produces high power tunable pulses at either the picosecond or 100-fsec pulsewidth depending on means of dispersion compensation. In a regeneratively mode-locked laser, a photo diode is used to monitor the C/2L mode beat from the laser cavity. This signal is used to drive an acoustooptic mode-locker in the cavity. If the cavity changes, the drive signal and the mode-locker follow automatically. When the laser is producing picosecond pulses and the drive to the mode-locker is turned off, the pulses continue for durations up to several hours. Using a Gires-Toumois interferometer (GTI) for dispersion compensation we have obtained 1.0-psec pulses and as much as 2.1 W of average power at a repetition rate of 82MHz. Over the entire tuning range from 710 to 900 nm we have produced over 1.5 W of 1.3-psec pulses. These pulses are transform-limited with a bandwidth of 0.49 nm. The pulses from this laser have been frequency doubled to produce 350 mW at 400 nm and pulse compressed to produce 50-fsec pulses. When the GTI is replaced by an intracavity prism pair we observe 105-fsec pulses with 700 mW of average power. These pulses are nearly transform-limited with a bandwidth of 6.8 nm.

© 1991 Optical Society of America