Optoelectronic oscillator based on a silicon microring modulator

An optoelectronic oscillator (OEO) system is built up with a high-speed silicon microring modulator. The modulator is based on a p-n doped ring resonator with a radius of 10 μm. Its electro-optic (EO) 3 dB bandwidth is ∼31.7 GHz, which makes it suitable for generating multi-GHz radio frequency signals. By using this modulator, one of the essential components of an OEO, the EO converter, has been dramatically miniaturized. At the same time, assisted by the ring resonator, the phase noise of the generated 10 GHz signal (nearly −90 dBc/Hz at 10 kHz offset) is not compromised compared to other integrated OEOs with mm footprint modulators. This is an important step toward a compact, scalable, and fully integrated silicon photonics-based OEO system together with our existing integrated light sources and photodetectors.