  We report a novel geometry for OPOs based on nonlinear microcavity
resonators. This approach relies on a self-locked scheme that enables OPO
emission without the need for thermal locking of the pump laser to the
microcavity resonance. By exploiting a CMOS-compatible microring resonator, we
achieve oscillation with a complete absence of shutting down, or
self-terminating behavior, a very common occurrence in externally pumped OPOs.
Further, this scheme consistently produces very wide bandwidth (>300nm, limited
by our experimental set-up) combs that oscillate at a spacing of the FSR of the
micro cavity resonance.
