Monolithic serial InGaAs-GaAs-AlGaAs laser diode arrays

Top-contact monolithic serially-biased InGaAs-GaAs-AlGaAs (λ~0.93 μm) broad area strained-layer quantum well laser arrays have been fabricated on a semi-insulating GaAs substrate. The laser array consists of four individual laser diodes and operates up to 2.8 W at 3.6 A (supply limited) per uncoated facet under pulsed conditions (15 kHz, 2 μs). The threshold current is ~0.5 A, and the peak slope efficiency and the peak electrical-to-optical conversion efficiency of an individual laser element are ~0.53 W/A and 14%, respectively. The near-field intensity distribution is shown to be broad enough to fill the entire active region under the p-metal stripe (125 μm) of the individual laser diodes at high current levels