High brightness 810 nm long cavity diode lasers with high d//spl Gamma/ ratio in asymmetric low confinement epitaxial structure

It is the aim of this report to show that asymmetric structures with high d//spl Gamma/ value can be manufactured and reliably operate. A series of epitaxial structures were designed and grown in the AlGaAs system. They all have a 7 nm QW designed for 810 nm emission. A graded confinement layer surrounds the QW. The asymmetric structures have an optical trap on the n side of the QW where another maximum of the radiation field distribution is trapped. The optical trap increases the extension of the radiation field existing outside of the QW and decreases the confinement factor. A second method to decrease the confinement factor is to use a p cladding layer with an increasing (stepwise) AlAs composition index, higher toward the p contact.