Monitoring and Tuning Micro-Ring Properties Using Defect-Enhanced Silicon Photodiodes at 1550 nm

We report on the application of defect-enhanced silicon waveguide photodiodes operating at 1550 nm as power monitors for use in photonic integrated circuits. In-line monitors of 250-μm length provide an efficiency of 97 mA/W by absorbing only 8% of the optical mode. The monitors were integrated onto micro-ring waveguide ports to provide measures of optical resonance characteristics and a feedback to a thermal resonance tuner. The suitability of these photodetectors for control of micro-ring resonators is demonstrated.