Few-cycle pulses with 40 W average power at 100 kHz from a flat-top pumped OPCPA

Area of Science:

• Laser Physics
• Nonlinear Optics
• Ultrafast Photonics

Background:

• Optical parametric chirped pulse amplification (OPCPA) is a key technique for amplifying ultrashort laser pulses.
• Existing OPCPA systems face challenges in achieving high average power with good beam quality.

Purpose of the Study:

• To develop and characterize a high average power OPCPA system delivering few-cycle pulses around 800 nm.
• To implement a novel scheme for generating a flat-top pump beam to improve energy transfer efficiency and minimize distortions.

Main Methods:

• Utilized an optical parametric chirped pulse amplification (OPCPA) setup.
• Implemented a novel, simple scheme for generating a flat-top pump beam.
• Operated at a 100 kHz repetition rate to achieve high average power.

Main Results:

• Achieved 40 W output average power (0.4 mJ/pulse) with few-cycle pulses around 800 nm.
• Demonstrated efficient pump-to-signal energy transfer with minimal spatio-temporal distortions.
• Reached a maximum output power of 60 W, with slightly reduced pulse quality.

Conclusions:

• The developed OPCPA system offers high average power and good pulse quality for ultrashort pulse generation.
• The novel flat-top pump beam generation scheme is effective for efficient and high-quality OPCPA.