Coherently Combined High Power Multicore Fibers

Fiber laser systems are known for being able to provide emission at high average powers. However, achieving pulsed operation with high peak-powers has been a challenge due to the small confinement of the light in the fiber causing limitations, e.g. due to nonlinear effects. As a strategy to overcome these limitations, parallelization using coherent combination of pulses emitted by multiple amplifier [1] has been worked on and has resulted in the achievement of record performance values [e.g. 2] so far. Recently, our focus has been multicore fibers which have the potential to allow for laser systems with a massive number of amplification channels while maintaining a compact footprint and manageable component count. In this contribution, we will show the latest results of performance values from Ytterbium-doped multicore fibers with $4\times 4$ and $7\times 7$ cores, respectively.