Continuous-wave mode-locked and dispersion-compensated femtosecond optical parametric oscillator

Abstract

We describe dispersion compensation of a cw mode-locked optical parametric oscillator based on a thin crystal of KTiOPO4 pumped intracavity by a standard colliding-pulse mode-locked dye laser, The device provides potential cw tunability from 0.72 to 4.5 μm with milliwatt outputs. Transform-limited pulses should be possible throughout the tuning range;here we report pulse widths of 105 fsec at 840 nm and 108 Hz. Active stabilization of the oscillator cavity is also discussed.