Controlled in-phase coherent coupling of laser array with monolithically-integrated arrayed Fourier filter

To achieve stable and robust in-phase coherent coupling optical field, a novel phase-locking edge-emitting laser array with reshaped double self-imaging (DSI) optical field is proposed and analyzed theoretically. A specificallydesigned arrayed Fourier filter (AFF) is monolithically integrated in the laser resonant cavity to realize the selectable mode self-injection (SMSI) and efficient self-injection of in-phase optical field. Then, the influences of edge-to-edge ridge-waveguide (RW) interval distance, number of laser emitter on steering the near-field pattern and far-field pattern characteristics are comprehensively investigated. And the designed laser array also exhibits the strong capability of maintaining high robustness of coherence even with imperfect periodicity. It is worth noting that the proposed method could be extended to large-scale two-dimensional laser array to generate fundamental lateral mode with in-phase optical field. Finally, our work demonstrates a feasible strategy of coherent output by tailoring the optical properties through structure modification, contributing to the advancement of coherent laser technology with enhanced stability and performance.