Diode Laser Efficiency Increases Enable > 400-W Peak Power From 1-cm Bars and Show Clear Path to Peak Powers in Excess of 1-kW

摘要

Peak optical power from single 1-cm diode laser bars is advancing rapidly across all commercial wavelengths. Progress in material performance is reviewed and we show that current trends imply there is no fundamental barrier to achieving peak powers of 1-kW per 1-cm diode laser bar. For bars with such high peak powers. commercially available reliable devices would be expected to deliver approximately 300-W per bar. Progress to date has allowed us to demonstrate > 400- W peak output from single 1-cm diode laser bars at emission wavelengths from 800-nm to 980-nm. The available range of emission wavelengths has also been increased. with 90-W bars shown at 660-nm and 24W at 1900-nm. complementing the 100-W bar previously demonstrated at 1470-nm. Peak power is seen to correlate closely peak efficiency. Further advances in diode laser efficiency and low thermal resistance packaging technology continue to drive these powers higher. The most critical improvements have been the reduction in the diode laser operating voltage though optimization of hetero-barriers (leading to 73% efficient 100-W bars on copper micro-channel) and a reduction in packaging thermal resistance by optimizing micro-channel performance (leading to < 0.2- degrees C/W thermal resistance).