Abstract
In this paper we discuss a technique for broadening the emission and gain spectra of 1.3 mu m quantum dot superluminescent light emitting diodes (SLEDs). By incorporating different amounts of indium in different wells of a multi-dot-in-well stack we are able to tailor the emission and gain spectra of the devices. This technique allows us to overlap the ground state of one dot-in-well (DWELL) with the excited state of another to achieve broader and flatter emission spectra compared to a SLED design comprising DWELL layers of constant indium composition. Due to the low internal loss of these structures, this broadening is achieved without a significant reduction in the output power of the devices. (c) 2006 American Institute of Physics.