Self-organized coherent laser array seems to be a promising method for coherent combining fiber lasers. Phase locking is
realized by mutual energy injection, without any active phase stabilization, requirement of the fiber length or the output
power for individual lasers.
In this paper, rate equations describing time evolution of the complex, slow varying electric field and gain of an array of
single transverse and longitudinal mode lasers proposed in former literature was referred to for modeling the self-organized
fiber laser array. The process for phase-locking evolution of each individual laser in a fiber laser array was
modeled and analyzed theoretically and numerically.
For the case of an array containing 2 or more than 4 lasers, the array will be in an out-of-phase mode, with a phase
difference of π between adjacent laser output modes. For an array containing 3 lasers, phase difference between adjacent
lasers would be ±2π/3. We will cite experiments to validate our verdict.
We can also obtain by investigating on the model that more powers can be extracted than the summation individual free
running lasers. Those phenomenons have been reported but not explained.
At the end of this paper, we perform system level analysis on the fiber laser array numerically. We find that with the
number of lasers increasing, the array will have a more critical condition on detuning frequency for phase locking.