Mutual injection-locking of two double-clad fibers for coherent beam combining with corner cube

摘要

We experimentally demonstrate coherent beam combination of two double-clad fiber lasers using mutual injection-locking in an external cavity coupling structure. The configuration employs a corner cube as a mutual injection component to couple the two lasers. A beam splitter acts as the output coupler and far field intensity has been observed at the lens focus plane. We observe interferential fringes with the contrast ratio of 0.5, and a combination efficiency of 80% is achieved. The total output power exceeds 11 W. We present simulative discussion here on the influence of multi-transversal modes of element beam. The multi-mode operation degrades the quality of the output beam of main peak power, fringe contrast ratio, and other parameters. The configuration has the potential to scale to more lasers without much structural modification.