Defect edge steepness dependence of multiple nonlinear hot-image formation from a single phase defect

Area of Science:

• Nonlinear optics
• Laser physics
• Optical engineering

Background:

• Nonlinear hot images limit high-power laser system performance.
• Typically, single defects produce one hot image peak, while multiple defects or media cause multiple peaks.

Purpose of the Study:

• To investigate the novel phenomenon of a single defect generating two nonlinear hot image peaks.
• To analyze the influence of defect edge steepness on hot image formation.

Main Methods:

• Numerical simulation using a super-Gaussian defect model to mimic edge steepness.
• Systematic investigation of factors like super-Gaussian order, defect size, modulation depth, and Kerr medium thickness.

Main Results:

• A single defect can produce two hot image peaks near the conjugate position when edge steepness is considered.
• The formation is attributed to the combined effects of hard-edge diffraction and self-focusing.
• Super-Gaussian order increases peak intensity; defect size significantly affects peak location.

Conclusions:

• The formation of double hot image peaks from a single defect is a critical, unexpected finding.
• This phenomenon poses a significant threat to optical components in high-power laser systems.
• Provides crucial insights for optical defect evaluation, component design, and beam quality control.