High-power long-wavelength (1.4 to 1.5 mm) laser array and stacked arrays

We have demonstrated record high cw and quasi-cw operation of InP-based 1.5 μm laser arrays (bars) and water-cooled stacks. High-efficiency and high-power operation were achieved through device design optimization including the multi-quantum well design, crystal growth process, doping profile, and material composition. Internal quantum efficiency, mode loss, gain parameters, and temperature sensitivity parameters are reported. Single-stripe devices produced 3 watts of cw output power and 35 percent electrical-to-optical efficiency. We demonstrated 40 watts of cw power from single bars on water-cooled copper-microchannel heatsinks. A stack of 20 bars that were collimated using fast axis microlenses achieved greater than 350 watts of cw power.