Differential Microring Modulators for Intensity and Phase Modulation for Optical Interconnects

We demonstrate a new concept of push-pull silicon microring modulator. Differential drive of two microring modulators nested in a Mach-Zehnder interferometer offers several advantages compared to conventional Mach-Zehnder modulators and single microring modulators for both intensity modulation and phase modulation. We experimentally demonstrate a low-chirp, low drive voltage and large extension ratio modulator for intensity modulation, and a low-chirp, drive-voltage insensitive modulator for phase modulation.