Silicon photonic micro-ring resonator dedicated to an optoelectronic oscillator loop

摘要

We present the design, fabrication and optical characterization of an ultra-long silicon ring resonator for opto-microwave applications. The investigated optical ring resonator has been fabricated under silicon-based processes using the silicon on insulator photonic platform. An add-drop ring resonator with integrated grating couplers was designed in the shape of a spiral in order to reduce the footprint of the device. After fabrication, the samples have been tested in the optical domain. At the wavelength of 1.55 urn, the optical transmission spectrum has shown a free spectral range (FSR) of 16 GHz which was in good agreement with the design target. The extinction ratio reached up to 19.5 dB for the drop port. Concerning the quality factor of the resonator, we got values up to 1.74 × 10~5. After these tests, a device has been selected to be introduced in the loop of an optoelectronic oscillator (OEO) system. Under these conditions it turned to be possible to generate oscillations with a peak at frequency of 16 GHz, showing a good agreement with the previously measured FSR.