COUPLED-STRIPE IN-PHASE OPERATION OF PLANAR NATIVE-OXIDE INDEX-GUIDED ALYGA1-YAS-GAAS-INXGA1-XAS QUANTUM-WELL HETEROSTRUCTURE LASER ARRAYS

High-performance, coupled-stripe, planar, index-guided AlyGa1-yAs-GaAs-InxGa1-xAs quantum-well heterostructure (QWH) laser arrays are fabricated by the formation of a relatively thick, current-blocking, native oxide from the high-gap AlyGa1-Yas upper confining layer between active stripes. Precise control of the thickness of the native oxide layer between emitters provides a means of varying the index step between stripes, and permits tailoring of the optical profile to produce in-phase operation. The 10-stripe coupled QWH laser arrays (approximately 3-mu-m-wide stripes on 4-mu-m centers) exhibit near-diffraction-limited, single-lobed, far-field patterns with low continuous (cw) thresholds (approximately 45 mA) and cw output powers (total external differential quantum efficiency > 50%) of over 100 mW per uncoated facet.