Adjustable slab-aberration compensator for high power slab laser.

Area of Science:

• Optics and Photonics
• Laser Technology
• Optical Engineering

Background:

• High-power lasers often suffer from inherent wavefront aberrations, limiting their beam quality and application potential.
• Compensating for these aberrations, particularly in the slab width direction, is crucial for advanced laser systems.
• Existing methods may lack the dynamic range or stability required for real-time correction in high-power laser environments.

Purpose of the Study:

• To propose and experimentally demonstrate an adjustable slab-aberration compensator (ASAC) for large-magnitude wavefront aberration correction.
• To optimize the ASAC design through simulations, considering mechanical and optical properties.
• To evaluate the ASAC's performance in compensating aberrations of a high-power Nd:YAG slab laser.

Main Methods:

• Design and simulation of an ASAC with 11 actuators and specific dimensions (130mm×45mm).
• Optimization of mirror coupling, actuator properties, and mirror thickness using simulation tools.
• Experimental integration and testing of the ASAC with a 20 kW Nd:YAG quasi-continuous wave (QCW) slab laser system.

Main Results:

• The ASAC demonstrated a dynamic range of 30 µm with initial surface figure PV and RMS values of 55 nm and 10 nm.
• Beam quality of the 20 kW Nd:YAG laser improved from 15× to 3.5× the diffraction limit after ASAC correction.
• The ASAC exhibited good thermal stability (temperature rise < 7°C) and maintained surface shape post-power shutdown.

Conclusions:

• The adjustable slab-aberration compensator (ASAC) is a viable solution for correcting significant wavefront aberrations in high-power slab lasers.
• The developed ASAC system enhances laser beam quality effectively, enabling improved performance in demanding applications.
• The ASAC's stability and robustness make it suitable for integration into industrial and research-oriented high-power laser systems.