Mismatch analysis of all-fiber coherent beam combiners based on the self-imaging effect

• Published in: High power laser science and engineering Vol. 12
• Main Authors: Yan, Yuefang, Liu, Yu, Zhang, Haoyu, Li, Yuwei, Guo, Chao, Shu, Qiang, Huang, Wenhui, Jing, Feng, Tao, Rumao
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.01.2024
• Subjects: all-fiber; Beam combiners; Coherence; coherent beam combination; Efficiency; Error analysis; Fiber lasers; Laser beams; Lasers; mismatch analysis; Power; self-imaging; coherent beam combination; self-imaging; all-fiber; mismatch analysis
• ISSN: 2095-4719; 2052-3289
• DOI: 10.1017/hpl.2023.88

All-fiber coherent beam combiners based on the self-imaging effect can achieve a near-perfect single laser beam, which can provide a promising way to overcome the power limitation of a single-fiber laser. One of the key points is combining efficiency, which is determined by various mismatches during fabrication. A theoretical model has been built, and the mismatch error is analyzed numerically for the first time. The mismatch errors have been numerically studied with the beam quality and combining efficiency being chosen as the evaluation criteria. The tolerance of each mismatch error for causing 1% loss is calculated to guide the design of the beam combiners. The simulation results are consistent with the experimental results, which show that the mismatch error of the square-core fiber is the main cause of the efficiency loss. The results can provide useful guidance for the fabrication of all-fiber coherent beam combiners.