Amplification of flat laser pulse train.

Area of Science:

• Laser Physics
• Accelerator Science

Background:

• Diode-pumped solid-state lasers are crucial for particle accelerators.
• Achieving uniform energy distribution in amplified laser pulse trains is challenging.

Purpose of the Study:

• To model and improve flattop amplification of laser pulse trains.
• To explain and mitigate energy variations within amplified pulse trains.

Main Methods:

• Developed a theoretical model incorporating the transverse Gaussian beam shape.
• Conducted experimental measurements on a diode-pumped Neodymium-doped Yttrium Lithium Fluoride (Nd:YLF) system.
• Verified the model's predictions regarding beam shape influence on pulse train flatness.

Main Results:

• The model successfully explained residual energy slopes in the pulse train.
• Experimental verification confirmed the impact of Gaussian beam profiles on pulse train flatness.
• Achieved a single-pass amplifier gain of approximately 7.
• Produced a flat output pulse train for up to 1000 infrared seed pulses.

Conclusions:

• The developed model accurately describes flattop amplification in Nd:YLF systems.
• Incorporating beam shape effects significantly enhances laser amplifier performance.
• The improved system is suitable for generating high-gain, uniform pulse trains for accelerator applications.