Optical distortions in end-pumped zigzag slab lasers.

Area of Science:

• Optics
• Laser Physics
• Materials Science

Background:

• End-pumped zigzag slab lasers are critical for high-power applications.
• Understanding optical distortions is essential for laser performance optimization.

Purpose of the Study:

• To investigate optical distortions in end-pumped zigzag slabs.
• To analyze the impact of thermal effects and birefringence on laser output.
• To determine optimal parameters for minimizing depolarization loss.

Main Methods:

• Ray tracing simulations were employed to calculate optical path differences.
• The Jones matrix technique was used to study depolarization dependence on phase retardance and slab cut angle.
• Experimental measurements of temperature and depolarization validated numerical findings.

Main Results:

• Significant optical distortions, including thermal lensing (effective focal length of meters) and edge effects, were identified.
• Depolarization increases rapidly with pumping power, though it remains below 3% at 10 kW for a specific Nd:YAG slab.
• An optimal phase retardance range (5°-13°) was found to minimize depolarization loss (<0.5%) for 0° or 60° cut slabs.

Conclusions:

• Thermal effects and stress birefringence significantly impact optical quality in zigzag slab lasers.
• Precise control over phase retardance and slab cut angle is necessary for efficient high-power laser operation.
• The study provides valuable insights for designing and improving high-power laser systems.