Chirped-pulse amplification in XeCl

Area of Science:

• Laser Physics
• Nonlinear Optics
• Excimer Lasers

Background:

• Understanding the saturation characteristics of laser amplifiers is crucial for optimizing laser performance.
• Excimer lasers, such as XeCl, are widely used in various scientific and industrial applications.

Purpose of the Study:

• To measure the effective saturation fluence (E(sat)) of a XeCl discharge amplifier using different pulse durations.
• To investigate the impact of pulse width and chirp on E(sat).

Main Methods:

• Experimental measurements of E(sat) using picosecond (ps) nearly transform-limited and strongly chirped pulses.
• Comparison of E(sat) values for 0.25-ps, 16-ps, and 75-ps pulses.
• Development and application of a rate-equation model incorporating gain bandpass variations and population decay.

Main Results:

• The effective saturation fluence (E(sat)) for a 16-ps pulse was comparable to that of a 0.25-ps pulse.
• Pulse stretching to 75 ps increased the effective E(sat) by 35%.
• Measured E(sat) values for longer pulses were lower than predicted for transform-limited pulses.

Conclusions:

• Pulse duration significantly influences the effective saturation fluence in XeCl amplifiers.
• A rate-equation model accurately predicts the observed E(sat) behavior, considering gain variations and population decay.
• The findings provide valuable insights for optimizing high-power excimer laser systems.