Conditions for parametric and free-carrier oscillation in SOI ring cavities with active carrier removal

摘要

We model optical parametric oscillation in ring cavities, focusing on silicon at 1.55μm, as a potential frequency-comb source for microwave and terahertz generation. Oscillation is possible if free-carrier absorption can be mitigated; this can be achieved using carrier sweep-out in a reverse-biased p-i-n junction to reduce the carrier lifetime. By varying the pump power, detuning, and reverse-bias voltage, it is possible to realize amplification in cavities with both normal and anomalous dispersion. Furthermore, a free-carrier self-pulsing instability leads to rich dynamics when the carrier lifetime is sufficiently long.