Quantum-limited timing jitter characterization of mode-locked lasers by asynchronous optical sampling

Area of Science:

• Optics and Photonics
• Laser Physics
• Metrology

Background:

• Ultra-low noise mode-locked lasers are critical for scientific advancements.
• Characterizing timing jitter in these lasers is essential for performance evaluation.
• Existing methods may lack the sensitivity for sub-femtosecond jitter analysis.

Purpose of the Study:

• To introduce a novel time-domain characterization method for timing jitter in ultra-low noise mode-locked lasers.
• To enable the measurement of sub-femtosecond period jitter using accessible electronics.
• To validate the method by determining the quantum-limited timing jitter of an Er-fiber laser.

Main Methods:

• Employing asynchronous optical sampling (ASOPS) for magnified timescale jitter statistics.
• Utilizing slow detectors and electronics (~100 MHz) for data acquisition.
• Performing period jitter histogram analysis and eye diagram analysis.

Main Results:

• Demonstrated a novel time-domain timing jitter characterization technique.
• Achieved accessibility to sub-femtosecond period jitter of optical pulse trains.
• Determined quantum-limited timing jitter for a passively mode-locked Er-fiber laser.
• Obtained a diffusion constant for pulse timing that aligns with theoretical predictions.

Conclusions:

• The developed ASOPS-based method is effective for characterizing ultra-low timing jitter in mode-locked lasers.
• This technique provides a practical approach to measuring sub-femtosecond jitter with standard equipment.
• The results validate the theoretical understanding of timing jitter in passively mode-locked fiber lasers.