US Patent 7573925 Semiconductor laser having a doped active layer

Semiconductor lasers having a doped active region. In one example embodiment, a laser includes a substrate and a doped active region positioned above the substrate. The doped active region includes a plurality of quantum wells separated by a plurality of barrier layers. The quantum wells and the barrier layers are doped with a doping material with a concentration between about 1*10^16/cm3 to about 1*10^17/cm3.