Self Imaging Configurations for Passive Global Coherent Laser Beam Combining

Parallel Laser Beam Combining is widely studied as a mean to overcome the physical limits of single laser sources. It can be obtained by injection coupling of several independent laser resonators. This of course represents a complex dynamical problem, the individual lasers being non-linear oscillators. Stable single phase solutions can be obtained for the entire system of lasers as well as local domains of phase-locked elements or chaotic behaviors. In passive systems the elements locking can be pursued by means of next-neighbor coupling or global feedback. We study self-imaging optical schemes for global feedback Coherent Beam Combining (CBC). We propose guided configurations to overcome edge-losses typical of this approach. Numerical Simulations indicate this as a viable solution for fiber lasers CBC.