Abstract:
Some possible approaches towards the generation of ultra-fast infra - red
COI laser pulses are discussed. Of these the technique of injection modelocking
in particular, which has been applied to a wide range of CO2 oscillators,
appear to be the most suitable for large aperture high power laser systems.
This technique, which essentially consists of the injection of a low power short
pulse into the slave laser cavity, to control the temporal behaviour of its emitted
radiation, has also permitted the wavelength control of non - dispersive
TEA CO2 laser systems, producing single wavelength ultra - fast CO2 laser
pulses in the GW power range. The experimental results obtained are reported
and compared with the predictions of a simple theoretical analysis. Regions
of broadening of the injected short pulse have been identified and the pulse
compression techniques employed to overcome this intrinsio broadening.
along with the simple theoretical models developed to analyse the various
pulse shaping effects in the amplifying medium, are also described.