  We consider an array of fiber lasers coupled through the nearest neighbors.
The model is a generalized nonlinear Schroedinger equation where the usual
Laplacian is replaced by the graph Laplacian. For a graph with no symmetries,
we show that there is no resonant transfer of energy between the different
eigenmodes. We illustrate this and confirm our result on a simple graph. This
shows that arrays of fiber ring lasers can be made temporally coherent.
