Y-Junction semiconductor laser arrays: Part II--Experiments

Laser arrays employing Y -junctions to coherently couple the emitters in-phase have been fabricated by metalorganic chemical vapor deposition. The far-field patterns are stable and centered normal to the facet. They are typically multilobed in accordance with the diffraction pattern of multiple emitters. By the use of flared waveguides near the facets the near-field fill factor can be increased to greater than 80 percent. This modification concentrates the radiation in the central diffraction lobe. Power outputs of 200 mW CW have been obtained from a ten element array of 1.5μm wide emitters.