Wave-breaking-extended fiber supercontinuum generation for high compression ratio transform-limited pulse...

Area of Science:

• Nonlinear Optics
• Ultrafast Photonics
• Fiber Optics

Background:

• Wave-breaking in optical fibers limits conventional pulse compression due to uncompensated chirp.
• Spectral broadening from wave-breaking has been largely unused for achieving shorter pulses.
• Standard prism or grating pairs struggle to compensate for the complex chirp generated by wave-breaking.

Purpose of the Study:

• To demonstrate that wave-breaking-free operation is not essential for achieving ultra-short pulses.
• To utilize the spectral extending capability of wave-breaking for pulse compression.
• To overcome limitations of conventional compressors in handling wave-breaking-induced chirp.

Main Methods:

• Propagating a 180 fs (FWHM) input pulse in a nonlinear photonic crystal fiber beyond the wave-breaking limit.
• Employing a 4f pulse shaper-based compressor to compensate for both linear and nonlinear chirp.
• Characterizing the supercontinuum output pulse duration and compression ratio.

Main Results:

• Achieved pulse compression of a wave-breaking-extended supercontinuum output pulse to 6.4 fs (FWHM).
• Demonstrated a high compression ratio of 28×.
• Showcased significant improvement compared to wave-breaking-free compression regimes.

Conclusions:

• Wave-breaking can be effectively utilized for ultra-short pulse generation when combined with advanced pulse compression techniques.
• A 4f pulse shaper is crucial for compensating the complex chirp, enabling unprecedented pulse compression.
• This approach offers a new pathway for generating few-cycle pulses with high compression ratios.