Experimental comparison of strained quantum-wire and quantum-well laser characteristics

Measured gain compression, differential gain, and damping of strained quantum wire lasers are reported and related to attributes specifically traceable to carrier confinement in two dimensions. A comparison is made with the properties of ridge lasers grown simultaneously. Damping and K factors are found to be comparable in the two structures. The differential gain is found to increase by two orders of magnitude (from 2.1×10−15 to 1.5×10−13 cm2), but the most significant consequence is an order of magnitude increase in gain compression (from 2.5×10−17 to 1.8×10−16 cm3), which limits the bandwidth. Carrier occupation, relaxation, recombination from multiple subbands, intersubband processes, high photon density, and consequent carrier heating and spatial hole burning effects in quantized structures are conjectured to cause some of the observed characteristics.