Multi-section ion-implantation-induced saturable absorbers for high-power 1.5-/spl mu/m picosecond laser diodes

To create the 1.5-/spl mu/m single-lobed Q-switched picosecond lasers with pulse energies over 50 pJ, we used a simple InGaAsP-InP double heterostructure with a 0.25 /spl mu/m thick active layer. This choice of active layer thickness was a compromise between the capacity for storing large carrier densities in the active layer and preserving single transverse mode operation. The ultrafast saturable absorber was created by high-energy heavy ion implantation; this method has been established as highly suitable for structures with thick active layer.