A novel strained quantum well laser emitting at 1.5 μm

The authors have grown a laser structure based on a In_xGa_1-xAs/In_yGa_1-yAs strained layer superlattice active region which emits at ~1.55 μm. An active region thickness of 44 nm gave the lowest threshold current density, J_th. This value of J_th is over an order of magnitude better than would have been obtained using a similar InGaAsP active layer thickness. This reduction in J_th for this thickness of active layer must be due to a reduction in the Auger processes. The high efficiency observed implies a reduction in optical losses. The lasers are considered for long haul telecommunications