Multicore Fibers with Interacting Cores for Coherently Combined High-Power Laser Systems

We demonstrate experimentally and numerically that in the multicore fiber with a square array of cores the out-of-phase supermode, which is stable at high power, can steadily propagate and can be coherently combined at the output with high efficiency. In numerical modeling 70 MW peak power can be achieved by using tapered active multicore fiber with an 11×11 array of cores.