Anti-resonant hollow-core fiber fusion spliced to laser gain fiber for high-power beam delivery

• Main Authors: Goel, Charu, Li, Huizi, Muhammad Rosdi Abu Hassan, Chang, Wonkeun, Yoo, Seongwoo
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Engineering::Electrical and electronic engineering; Optical Fibre; Coupling Efficiency
• Online Access: https://hdl.handle.net/10356/156841
• Institution: Nanyang Technological University

We present the selective excitation of the fundamental mode in an anti-resonant hollow-core fiber (ARHCF) fusion-spliced with a commercial large mode area (LMA) fiber. By designing and fabricating a single-ring ARHCF that is mode-matched to a LMA fiber and by splicing the two using a CO2 laser-based splicer, we achieve a coupling efficiency of 91.2% into the fundamental mode. We also demonstrate an all-fiber integration of an ARHCF with a commercial ytterbium-doped fiber in a laser cavity for beam delivery application. Coupling of the single-mode laser output beam into the fundamental mode of the ARHCF is demonstrated with 90.4% efficiency (<0.45dB loss) for up to 50 W continuous wave beam in a stable and alignment-free all-fiber laser setup.