Characterization and Analysis of 1.3-μm InAs/InGaAs Self-Assembled Quantum Dot Lasers

High performance 1.3-μm GaAs-based InAs/InGaAs quantum dot (QD) lasers have been fabricated. The QD lasers have demonstrated low threshold current, high output power as well as high temperature operation. Temperature-dependent (20-100°C) and excitation power-dependent (12-700 mW) photoluminescence (PL) measurements have been carried out on the QD laser structures. Both ground state (GS) and excited state (ES) luminescence has been observed in the PL spectra as well as in the lasing spectra. Rate equations were used to interpret the PL behavior of the QD structures. High radiative recombination efficiency in the QD structure has been verified even at 100°C. The excitonic modal gain has been calculated and compared with the experimentally obtained modal gain value by the Hakki-Paoli method from the QD laser with good agreement.