Low threshold current 1.5- mu m buried heterostructure lasers using strained quaternary quantum wells

Buried heterostructure lasers operating at a wavelength of 1.5 mu m with four compressively strained quaternary quantum wells (strain approximately 1.8%, thickness approximately 90 AA) and current blocking layers were made using atmospheric pressure metalorganic chemical vapor deposition. Pulsed room-temperature threshold currents for uncoated devices as low as 4.1 mA and as low as 0.8 mA for devices with high reflectivity mirror coatings are reported. The dependence of threshold current on active region width is consistent with broad-area laser measurements.<
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