Self-Forced Silicon Photonic Integrated Optoelectronic Oscillators using High-Q Filtering Delay Lines

A Si-photonic integrated forced optoelectronic oscillators (OEO) is presented using integrated delays for a combination of optical self-injection locking (OSIL) and dual self-phase-locked loop (DSPLL). An RF signal detection of an optical phase modulation (PM) realized using 2D photonic crystal (PhC) structure with defects is demodulated using a phase to intensity (PM-IM). The combined transceiver is integrated with a similar 2D PhC structure realized as optical cavity is employed to realize an OEO. Performance of this free-running OEO is modeled in terms of close-in to the carrier phase noise; further improvement in frequency stability is demonstrated using self-forced injection locking and phase locking processes. Integrated delay lines are added to force oscillate OEO using various order of optical add-drop filter (ADF) resonators. Optimized feedback levels for OSIL and optimized loop filter gain for SPLL are identified, respectively. A phase noise reduction of 47 dB is predicted to phase noise level of -85 dBc/Hz at 1 kHz offset for oscillation frequency of ~ 1.2 GHz using a 13 ns delay of OSIL combined with DSPLL delays of 17 ns and 25 ns respectively.