Coherent optical pulse evolution in a CO2 amplifier

• Published in: Optics communications 1976-04, Vol.17 (1), p.32-37
• Main Authors: Hamadani, S.M., Kurnit, N.A., Javan, A.
• Format: Article
• Language: English
• ISSN: 0030-4018
• DOI: 10.1016/0030-4018(76)90173-5

Coherent reshaping of short optical pulses (2-5 nsec) in a low-pressure CO2 laser amplifier is studied experimentally. A zero-degree pulse formed by introducing a 180 deg phase reversal in an optical pulse, and amplifying the phase-reversed portion of the pulse for times comparable to the transverse relaxation time, is applied to an amplifying medium. The long tail resulting from amplification of the short pulse is terminated by application of the phase-reversed pulse. These results were obtained in a linear intensity regime, but can be extended to the nonlinear regime. Effects prominent in the amplification of subnanosecond pulses in high-pressure laser amplifiers can be studied by the method. Off-resonant amplification of short pulses can be studied by tuning the laser to oscillation in the wing of the gain profile. Numerical calculations are given for pulse amplification in the nonlinear regime in high-pressure CO2 amplifiers.