808-nm laser diode bars based on epitaxially stacked double heterostructures

We have fabricated and investigated linear arrays of single laser diodes (LDs) and epitaxially stacked double LDs based on AlGaAs/GaAs heterostructures emitting in the 808-nm range. The power — current characteristic of the double-LD bars has a slope of 2.18 W A^-1, which is almost twice that of the single-LD bars (1.16 W A^-1). The voltage drop across the former bars is also larger. At a pump current of 60 A, the output power of 5-mm-long arrays of LDs based on epitaxially stacked double heterostructures is 100 W under quasi-cw pumping, which is a factor of 1.8 above that of the single-LD bars under identical conditions.