Dynamics of Passively Phased Ring Oscillator Fiber Laser Arrays

In this paper, we study fiber laser arrays coupled in a spatially filtered ring oscillator geometry that produces a tiled-array output. In particular, we examine the passive phasing dynamics, the efficiency of coherent combination, and the dependence of the system´s behavior on nonlinearities in the fibers. For an array containing a small number of elements, we find that the fibers achieve a co-phased state within two round trips after a perturbation. Steady-state results agree with the previous work. We also find that the Kerr nonlinearity decreases the combining efficiency as determined from the on-axis intensity in the far-field output.