Optimized Multicore Fiber Designs for Coherent Combination

Multicore fibers (MCFs) have already demonstrated to be a power-scalable fiber laser concept with recent demonstrations reaching the 1 kW level [1]. MCFs help getting around most of the limitations of conventional fiber laser systems by distributing the amplification load among many cores. Hereby, in most systems, a single seed beam is split up into N different sub-beams that are amplified in the cores of the MCF. After amplification, all the sub-beams are coherently combined into a single beam, which properties (average power, pulse energy, beam quality, etc) could not be reached with single core fibers [2].