Abstract

High-power operation of an InGaAs/GaAs laser emitting at 0.98 µm is of great interest in applications such as optical pumping of Er-doped fiber amplifiers. Power outputs of ~100 mW have been reported in a ridge waveguide structure.^1,2 In this paper we report on the high-power and high-efficiency operation of buried-heterostructure (BH) graded-index separated-confinement-heterostructure (GRINSCH) strained-layer single-quantum-well (SSQW) lasers. A high-reflectivity (~0.9) coating was applied to the rear facet, and a low-reflectivity (~0.05) coating was applied to the front facet. The lasers were tested in a junction-up mounting configuration. Owing to the excellent two-dimensional carrier and optical confinement of the BH-GRINSCH structure, the lasers are able to deliver optical powers in excess of 250 mW at room temperature over the entire spectrum of 0.87µm ≤ λ ≤ 1 µm. The highest power measured was 330 mW with an external quantum efficiency of 84%. The lasers operate in a stable single transverse mode to as great as the maximum power level with a beam divergence of ~20° (parallel to the junction plane). The characteristic temperature of these lasers was found to be as high as ~120 K, and output powers of over 120 mW were measured at ~90°C.

© 1990 Optical Society of America