Integrating III-V quantum dot lasers on silicon substrates for silicon photonics

The realization of efficient III-V lasers directly grown on Si substrates is highly desirable for large-scale and low-cost silicon based optoelectronic integrated circuits. However, it has been hindered by the high threading dislocation (TD) density generated at the interface between III-V compounds and Si substrates. Introducing dislocation filter layers (DFLs) to suppress the TD propagation into the active region becomes a key factor for realising lasers with advanced performance. In this paper, optimization of InGaAs/GaAs DFLs in III-V quantum dot (QD) lasers on Si is demonstrated. Based on these optimized DFLs and other strategies, we have achieved a high performance electrically pumped QD laser on a Si substrate with threshold current density of 62.5 A cm(-2), over 105 mW output power, maximum operation temperature of 120 degrees C and over 100,158 h of extrapolated lifetime.