Above 45 W thermal lens compensated acousto-optically Q-switched Tm:YAP laser

Area of Science:

• Optics and Photonics
• Laser Physics
• Materials Science

Background:

• High-power 2 μm lasers are crucial for various applications.
• Thulium-doped lasers (Tm:YAP) face challenges with thermal lensing.
• Effective thermal management is key for high-power solid-state lasers.

Purpose of the Study:

• To demonstrate a high-power Q-switched 2 μm laser.
• To address the severe thermal lensing issue in Tm:YAP crystals.
• To achieve a robust and stable laser cavity design.

Main Methods:

• Utilized a thermal lens compensated cavity design.
• Employed an acousto-optically Q-switching scheme.
• Investigated laser performance across various pulse repetition frequencies.

Main Results:

• Achieved a maximum average output power of 45.8 W at 1937 nm.
• Obtained a pulse duration of 64 ns at a pulse repetition frequency of 20 kHz.
• Demonstrated a stable cavity with a broad tolerance to cavity length deviations.

Conclusions:

• This work presents the highest reported nanosecond Q-switched laser power for solid-state Tm lasers.
• The developed laser offers a pathway for high-power Q-switching in quasi three-level lasers.
• The laser is suitable for applications like lidar, surgery, and polymer processing requiring high-repetition-frequency pulsed 2 μm sources.