We report a factor-of-6 shortening of the 240-ps (FWHM) pulses in a triple-pass, 2.5-atm CO<sub>2</sub> amplifier. This technique is based on the self-phase modulation of a 10-μm pulse in a plasma after the first pass of amplification, followed by narrowing of this chirped pulse during further amplification. Subsequently, strong power broadening provides the necessary bandwidth to amplify 40-ps pulses to terawatt power levels.
© 2001 Optical Society of America
(140.3280) Lasers and laser optics : Laser amplifiers
(140.3440) Lasers and laser optics : Laser-induced breakdown
(140.3470) Lasers and laser optics : Lasers, carbon dioxide
(190.5940) Nonlinear optics : Self-action effects
S. Ya. Tochitsky, C. Filip, R. Narang, C. E. Clayton, K. A. Marsh, and C. Joshi, "Efficient shortening of self-chirped picosecond pulses in a high-power CO2 amplifier," Opt. Lett. 26, 813-815 (2001)