Low-threshold high-efficiency laser diodes with aluminum-free active region

摘要

Semiconductor diode lasers include an aluminum free active region including at least one active layer having a general composition In.sub. (1-x) Ga.sub.x As.sub.y P.sub.(1-y) where 0≦y≦1; two confinement layers bounding the active region and having a general composition In.sub.(1-x) (Ga.sub.(1-z) Al.sub.z)x P wherein aluminum content z may be zero; and a lower cladding layer, and at least one upper cladding layer adjacent the confinement layers. The cladding layers have the same general composition as the adjacent confinement layer, but always have a finite aluminum content. The aluminum content of the cladding layers is selected such that the cladding layers have a energy bandgap greater than the energy bandgap of the confinement layers.