CW FEMTOSECOND PULSES TUNABLE IN THE NEARINFRARED AND MIDINFRARED

Continuous tuning of a cw femtosecond optical parametric oscillator (OPO) is demonstrated from 0.755-1.04-mu-m for the signal branch, and from 1.5-3.2-mu-m for the idler branch, covering most of the potential tuning range of the device. Transform-limited pulses under 120 fs in duration are found throughout the signal tuning, and idler pulsewidth measurements suggest pulses of less than 215 fs should be possible throughout the idler tuning. These results have been achieved using a new walkoff compensation scheme in the OPO. Preliminary results of transmission correlation measurements of carrier relaxation in InGaAs are presented using the parametric oscillator as a tunable excitation source.