A Time-Division-Multiplexing Scheme for Simultaneous Wavelength Locking of Multiple Silicon Micro-Rings

This paper presents a time-division-multiplexing (TDM) scheme for simultaneous wavelength locking of multiple silicon micro-rings by exploiting the speed mismatch between the heater and the controller. This scheme could reduce the overall chip size significantly without reducing the wavelength lock speed. It also avoids cross-channel coupling using the least number of ADCs and DACs. The simplest TDM scheme involving two micro-rings is experimentally verified using board-level circuits. Theoretically, this approach can be scaled to even hundreds of micro-rings, pointing out a way towards large-scale integrated optoelectronics, which is required by many important applications, such as wavelength division multiplexing for chip-to-chip optical I/O.