Low-threshold-current, high-quantum-efficiency 1.5 mu m GaInAs-GaInAsP GRIN-SCH single quantum well laser diodes

The authors fabricated 1.5 mu m GaInAs/GaInAsP graded index, separate confinement heterostructure (GRINSCH) single-quantum-well buried heterostructure laser diodes (LDs) by metalorganic chemical vapor deposition. The LDs exhibit a low internal loss of 4.3 cm/sup -1/, a high quantum efficiency of 37-40%/facet, and a high light output power of 109 mW. A very low threshold current of 6.2 mA and a high characteristic temperature of 94 K were obtained by facet coating. The perpendicular far-field angle is 26-32 degrees , which is smaller than that of GRINSCH multiple-quantum-well LDs. These LDs oscillated at the n=1 quantized level, not at the n=2 quantized level.<
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