High-Power InGaAlP Laser Diodes for High-Density Optical Recording

Theoretical investigation has been carried out for high-power InGaAlP visible-light laser diodes. The thin active layer, essential for preventing catastrophic optical damage of the laser facet, enhances carrier overflow and causes a deterioration in temperature characteristics. Increase in the bandgap energy difference between the active layer and the cladding layer is required in order to maintain sufficient heterobarrier height. High acceptor concentration for a p-cladding layer has a great effect on the prevention of the carrier overflow and, as a result, on the improvement of the temperature characteristics. High-power transverse-mode stabilized InGaAlP lasers, operating at high temperature, were realized by employing a composition-shifted thin active layer and a highly doped p-cladding layer. High-power operation, at over 100 mW, was achieved.