22-W average power high pulse energy multipass-cell-based post-compression in the green spectral range

Area of Science:

• Laser physics
• Nonlinear optics
• Ultrafast optics

Background:

• Ultrashort pulse generation is crucial for advanced scientific applications.
• Existing post-compression techniques are primarily optimized for the near-infrared spectrum.
• Extending ultrashort pulse capabilities into the visible spectrum remains a significant challenge.

Purpose of the Study:

• To demonstrate a gas-filled multipass-cell-based post-compression system for visible wavelength ultrashort pulses.
• To achieve high pulse energy and average power at 515 nm with high efficiency.
• To explore the potential of visible ultrashort pulses for advanced light source development.

Main Methods:

• Utilized a gas-filled multipass cell for post-compression of 515 nm second-harmonic pulses from an Yb:fiber laser.
• Optimized gas composition and cell geometry for efficient pulse shortening.
• Characterized pulse duration, energy, average power, and overall efficiency.

Main Results:

• Successfully compressed pulses from 240 fs to 15.7 fs at 515 nm.
• Achieved 0.44 mJ pulse energy and 22.4 W average power at a 50.8 kHz repetition rate.
• Demonstrated an overall system efficiency exceeding 40%.

Conclusions:

• Gas-filled multipass-cell post-compression is effective for generating energetic ultrashort pulses in the visible regime.
• The developed system overcomes limitations of previous methods in the visible spectrum.
• This advancement opens possibilities for high photon flux higher-order harmonic generation sources in the green spectral range.