Silicon photonics promises scalable manufacturing of integrated photonic devices through utilization of established CMOS processing techniques and facilities. Unfortunately, the silicon photonics platform lacks a viable light source, which has historically been overcome through heterogeneous integration techniques. To further improve economic viability, the platform must transition to direct epitaxy on Si to bypass the scaling limits imposed by the small sizes and high cost of III-V substrates in heterogeneous integration. InAs quantum dots have demonstrated themselves as the most promising candidate for achieving high performance light emitters epitaxially grown on Si. Using molecular beam epitaxy, we have grown quantum dot lasers composed of InAs dot-in-a-well active layers on industry-standard, on-axis (001) Si substrates. In this report, we utilized p-doping of the quantum dot active region to increase gain for improved dynamic performance and reliability. These devices have been subjected to accelerated aging conditions at 60°C and a bias multiple of twice threshold current density. After 2,750 hours of continuous aging, an extrapolated lifetime of more than 100,000 hours has been calculated.
The performance of single photon sources based on single quantum dot emitters coupled to microcavities is analyzed with respect to different conditions of polarization. Electro-optic tuning is shown as a method to tune microcavities with distributed Bragg reflector mirrors into polarization degeneracy. Typically, for large cavity polarization splitting, excitation in the linearly polarized cavity modes is the only viable method for resonantly driving a single photon source. However, polarization degenerate cavities allow for arbitrary polarization conditions. A semi-classical model is used to analyze the performance of single photon sources under different polarization conditions. Further, the effect of residual cavity polarization splitting is analyzed under pulsed excitation.