Controlling Nonlinear Interaction in a Many-Mode Laser by Tuning Disorder.

Area of Science:

• Nonlinear optics
• Many-body physics
• Laser physics

Background:

• Many-mode lasers with nonlinear modal interactions are valuable for studying many-body physics.
• Controlling interaction strength in such systems over a wide range is a significant challenge.

Purpose of the Study:

• To present a novel method for controlling lasing mode structures.
• To enable precise and continuous tuning of interaction strength in many-mode lasers.

Main Methods:

• Introducing random phase fluctuation to a nearly degenerate laser cavity.
• Numerical simulations and experimental validation.

Main Results:

• Decreasing the characteristic scale of phase fluctuation fragmented transverse modes.
• Reduced spatial overlap of modes suppressed modal competition for gain.
• More lasing modes were observed with the controlled phase fluctuation.

Conclusions:

• The developed system offers tunability, flexibility, and robustness for investigating many-body phenomena.
• This method provides a powerful platform for advancing research in complex physical systems.