Design optimization of high performance single-mode fabry-perot lasers based on quantum dot materials

The interplay of inhomogeneous and homogeneous broadening of InGaAs/GaAs quantum-dot (QD) Fabry-Perot laser is discussed by a comprehensive rate-equation model. It is found that for a given inhomogeneous broadening, there is always an optimum homogeneous broadening which leads to a narrowest output power spectrum. With the optimum values, the single longitudinal-mode laser is designed. For a cavity length of 200μm, a SMSR (side-mode suppression ratio) of 41.65dB and 3dB bandwidth of 17GHz are obtained under 5mA driving current. Moreover, to get a SMSR over 38dB, the inhomogeneous broadening should be lower than 17meV. This work can provide a quantitative reference basis for the single-mode quantumdot laser design. © OSA/ANIC/IPR/Sensors/SL/SOF/SPPCom/2011.