Related Experiment Video
Updated: May 27, 2025
10:17
20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
11.4K
2.05 μm high-energy thulium-doped fibre amplifier based on backward pumping
Chao Yang1, Bowen Zheng2, Junyu Huang2
1The School of Opto-electronics Engineering, Changchun University of Science and Technology, Changchun, 130022, Jilin, China. yc_super1@163.com.
Scientific Reports
|February 15, 2025
Summary
This study presents a thulium-doped fiber amplifier (TDFA) achieving 33.4 W CW and 3.86 mJ pulsed output at 2.05 μm. The novel design enhances stability and protects against high-energy seed lasers.
Area of Science:
- Lasers and Photonics
- Optical Engineering
- Materials Science
Background:
- Thulium-doped fiber amplifiers (TDFAs) are crucial for generating high-power output in the 2-micron wavelength range.
- Existing TDFA designs often face challenges with structural complexity, optical losses, and protection against high-energy seed lasers.
- Efficient amplification at 2.05 μm is essential for various applications, including medical procedures and remote sensing.
Purpose of the Study:
- To demonstrate a novel, simplified, and robust thulium-doped fiber amplifier (TDFA) for high-power laser output.
- To investigate the performance of the TDFA in both continuous wave (CW) and Q-switched modes.
- To evaluate the effectiveness of a new spatial coupling system and integrated fiber end cap design.
Main Methods:
- Utilized a Ho:GdVO4 solid-state laser operating at 2048.53 nm as the master oscillator.
- Implemented a novel spatial coupling system with a single lens and curved end cap for reduced losses and simplified structure.
- Employed backward pumping in the power amplifier (PA) stage for direct, pure laser output and integrated fiber end cap for seed laser protection.
Main Results:
- Achieved a maximum CW output power of 33.4 W with a slope efficiency of 19.5% at 2048.57 nm.
- In Q-switched mode, obtained a maximum single pulse energy of 3.86 mJ at 5 kHz PRF, with a pulse width of 22.1 ns, peak power of 174.7 kW, and average power of 19.3 W.
- Observed stable output without nonlinear optical effects like SRS or SBS, demonstrating the system's robustness.
Conclusions:
- The developed TDFA, utilizing a novel coupling system and backward pumping, offers a simplified, efficient, and stable high-power 2.05 μm laser source.
- The integrated fiber end cap design effectively protects the fiber core from damage by high-energy seed lasers.
- The demonstrated performance in both CW and Q-switched modes highlights the potential of this TDFA for demanding applications.
