Self-stabilization of fundamental in-phase mode in resonant antiguided laser arrays

The effect of gain spatial hole burning on antiguided arrays is analyzed for the first time. Nonresonant devices, due to the nonuniformity of the in-phase-mode intensity profile, experience self-focusing and multimode operation with increasing drive level, similar to the behavior of evanescent-wave-coupled devices. Resonant and near-resonant devices [i.e., resonant-optical-waveguide (ROW) arrays], due the uniformity of the in-phase mode, display some mild defocusing with increasing drive level, while the nearest high-order mode cannot reach threshold to drive levels in excess of 4× threshold. These results explain the fundamental single-mode stability of ROW arrays, in excellent agreement with experimental data.