Broad-band superluminescent diodes fabricated on a substrate with asymmetric dual quantum wells

Broad-band AlGaAs-GaAs superluminescent diodes are fabricated using asymmetric dual quantum wells. With a proper design of the quantum-well structure, the spectral width of the superluminescent diodes could be engineered. By choosing 40 /spl Aring/ and 75 /spl Aring/, respectively, for the two quantum wells, the spectrum remains bell-shaped and is broadened to 2/spl sim/3 times that of the conventional superluminescent diodes. The measured spectra show that there is no obvious preference on the transition in either well at any pumping current.