Entrainment of solid-state laser arrays

We find that the natural antiphasing tendency in linear solid-state laser arrays can be overcome by an injected field, even if the N elements are not identical. We derive a condition for full entrainment that agrees well with numerical simulations using experimentally accessible parameters. The resulting output intensity saturates near the maximum coherent value of ${\mathit{N}}^2$ times that of a single laser. We find that the entrained output can be modulated in a prescribed manner by a suitable choice of the injected field.