High Power, high reliability CW and QCW operation of single AlGaAs laser diode array design

A single laser diode bar design, based on the AlGaAs material system, has been developed for high power, high reliability operation at a variety of CW and QCW operating conditions. The bar has a cavity length of 750 mu m and a fill factor of 40%. Typical CW operation has a threshold current of similar to 10A and a conversion efficiency of >45% at 40W. A variety of lifetests have been conducted at both CW and QCW operating conditions from the same bar design. On-going 3000hr CW operation at 45C and 40W shows an extrapolated median lifetime (20% current increase) of 16,500hrs at 45C or similar to 50,000hrs at 25C (with 0.45eV activation energy). On-going 3000hr QCW operation at 60C/60W and 35C/100W, with a pulse width of 200 mu s and a duty factor of 2%, shows a median lifetime of similar to 10 billion shots and similar to 5 billion shots, respectively. In addition to single bar operation, this bar design can be stacked in various 2-D configurations. A 4 bar linear stack operating at 160W CW and a 6 bar vertical stack operating at 240W CW have been developed with superior performance. Results for high duty and low duty QCW stacks will also be presented.