Simplifying multicore fiber laser systems

Multicore fibers have redefined expectations on the performance level that can be reached by fiber lasers, with multi-kW, Joule-class systems already in development. This remarkable leap in performance is due to the fact that multicore fibers, due to their tight integration of the channels, allow solving some of the main issues of beam combining such as, for example, the linear dependence of cost, size and complexity on the channel count of such systems. In spite of this, multicore fiber lasers are still complex systems that require careful beam splitting and recombination stages and, in their current implementation, need to be actively stabilized. In this work we will show a design of multicore fibers that can help to reduce the overall complexity of the system by significantly simplifying the splitting and recombination stages as well as offering the possibility of passively stable operation.