Amplification of phase-modulated ultrashort pulses of infrared radiation in a CO2 amplifier

An investigation was made of the influence of phase modulation of picosecond pulses on their amplification in a CO₂ amplifier. Linear frequency modulation of the input pulses was not maintained during amplification. This casts doubt on the possibility of compressing such amplified pulses. However, amplification of chirped picosecond pulses in a CO₂ amplifier makes it possible to generate a train of ultrashort pulses with a high ( ~ 10¹² Hz) and controlled repetition frequency.