Study of chirped quantum dot superluminescent diodes

Abstract

Superluminescent diodes (SLDs) utilizing an InAs chirped quantum dot (QD) active layer were fabricated. The chirped QD active layer was designed as a three-stack InAs QD part with a band-gap energy of 0.95 eV and another three-stack InAs QD part with a band-gap energy of 1.03 eV. From the electroluminescence (EL) measurement of SLDs, it was observed that there were two peaks separated by 80 run. Such separation of the two peaks was consistent with that shown in the photoluminescence curve obtained at room temperature, indicating that the chirped QD characteristics of the active layer are directly reflected on the EL spectra of SLDs. The 3 dB bandwidths of both peaks were measured a 30 nm and 37 nm.