A Systematic Thermal Control Scheme for Microring-Based Optical Filters

We demonstrate a systematic thermal control scheme for microring-based optical filters. The detailed thermal interactions between the different elements of the optical filters-characterized by two thermal calibration matrices-have been successfully measured to understand the thermal behaviors of these waveguide-based optical filters. The effectiveness of controlling microring-based optical filters using these thermal calibration matrices is illustrated by a third-order lattice ring and a double-ring-assisted Mach-Zehnder interferometer.