Extreme events and single-pulse spatial patterns observed in a self-pulsing all-solid-state laser

Area of Science:

• Nonlinear optics
• Laser physics
• Complex systems

Background:

• Passively Q-switched, self-pulsing all-solid-state lasers are widely used.
• These lasers exhibit diverse dynamical regimes, including chaos and extreme events (EEs).
• The formation mechanism of EEs, or dissipative optical rogue waves, in these lasers remains unclear.

Purpose of the Study:

• To directly observe the pulse-to-pulse evolution of transverse patterns in a passively Q-switched laser.
• To investigate the relationship between transverse patterns and the occurrence of EEs.
• To understand the deterministic nature of EEs for potential chaos control.

Main Methods:

• Direct observation of transverse patterns and pulse intensities.
• Analysis of pattern evolution across different dynamical regimes (periodic and chaotic).
• Correlation analysis between pulse intensity sequences and transverse patterns.

Main Results:

• Periodic regimes show intensity-pattern correlations.
• Chaotic regimes involve alternating patterns, with EEs linked to a few specific patterns.
• Pre- and post-EE pulse intensities and patterns exhibit significant repetitiveness.
• EEs were observed to arise from systems with few interacting transverse modes.

Conclusions:

• Extreme events in this laser system follow a deterministic evolution.
• EE formation is directly linked to specific, repeating transverse patterns.
• Understanding this deterministic behavior is crucial for developing mathematical models and controlling EEs in lasers.