Li Yunchu, Zhang Lin, Song Muping, Zhang Bo, Yang Jeng-Yuan, Beausoleil Raymond G, Willner Alan E, Dapkus P Daniel
Dept of Electrical Engineering, Univ of Southern California, Los Angeles, CA 90089, USA.
Opt Express. 2008 Aug 18;16(17):13342-8. doi: 10.1364/oe.16.013342.
A compact silicon coupled-ring modulator structure is proposed. Two rings are coupled to each other, and only one of these rings is actively driven and over-coupled to a waveguide, which enables high modulation speed. The resultant notch filter profile is steeper than that of the single ring and has exhibited a smaller resonance shift and lower driving electrical power. Simulation results include: (i) potentially 60-Gb/s non-return-to-zero (NRZ) data modulation and over 20-dB extinction ratio can be achieved by shifting the active ring by a 20 GHz resonance shift, (ii) the frequency chirp of the modulated signals can be adjusted by varying the coupling coefficient between the two rings, and (iii) dispersion tolerance at 0.5-dB power penalty is extended from 18 to 85 ps/nm, for a 40-Gb/s NRZ signal.
