We solve the time-independent (o.d.e.) propagation equations for the c.w. operation of an array of externally coupled
fiber amplifiers with internal reflection, in which Kerr and resonant nonlinearities play a part. A transcendental equation
for each amplifier is obtained, collectively yielding multiple distinct array solutions, which are characterized in terms of
their mutual phase coherence. We find that the two types of nonlinearity (Kerr and resonant) affect the solutions in
distinct parameter regimes. The relation of Strehl ratio to output power at fixed wavelength and feedback level reveals
that phase-locking may occur due to nonlinearity as opposed to mode selection, in accordance with recent experiments
(H-S Chiang, J.R. Leger, J. Nilsson and J. Sahu, Optics Letters (2013)). The individual lasing instability (“rogue”
lasing) anticipated by A.E. Siegman in 2004 we observed only at low feedback levels in a small number of cases.
A coherent fiber laser array in a Self-Fourier cavity is described. The Self-Fourier cavity has been shown to coherently
combine an array of fiber lasers through its ideal supermode discrimination as a result of its passive coupling matrix of
rank 1. Recently, a static model has been developed that extrapolates this technique to an array of very large number of
fiber lasers by exploiting the gain-dependent phase shift and incorporating specific levels of individual feedback to each
fiber amplifiers, transforming them into regenerative amplifiers. By engineering the resonator in the manner described
here, this enables us to circumvent predicted scaling limits and offers the possibility to achieve a highly phased state for
a large number of fiber lasers in such an array. Experimental results are presented, the model of operation is discussed,
and scaling predictions are presented.