Few-cycle nonlinear pulse compression in a dispersion-engineered folded multi-pass cell

Area of Science:

• Optics and Photonics
• Ultrafast Lasers
• Nonlinear Optics

Background:

• Achieving few-cycle pulses is crucial for advanced scientific applications.
• Existing methods for pulse compression often face limitations in power, footprint, or efficiency.

Purpose of the Study:

• To develop a dispersion-engineered folded multi-pass cell (MPC) for efficient few-cycle nonlinear pulse compression.
• To achieve high average power and high throughput ultrashort pulses in a compact system.

Main Methods:

• Utilized a folded multi-pass cell (MPC) design with multiple reflections on plane mirrors.
• Integrated dispersion management by incorporating an off-the-shelf chirped mirror.
• Leveraged self-phase-modulation (SPM)-dominated spectral broadening for nonlinear pulse compression.

Main Results:

• Delivered 10.7 fs pulses with 11 W average power at a 200 kHz repetition rate.
• Achieved a high throughput of 92% and near-diffraction-limited beam quality (M²∼1.3).
• Demonstrated efficient compression into the few-cycle regime without spectral broadening saturation in a compact footprint (0.55 × 0.15 m²).

Conclusions:

• The dispersion-engineered folded MPC is a highly effective system for generating ultrashort few-cycle pulses.
• The compact design and high performance make it suitable for various scientific and technological applications.
• This approach overcomes limitations of spectral broadening saturation in nonlinear pulse compression.