Low power consumption silicon photonics tuning filters based on compound microring resonators

Abstract

Scalable integrated optics platforms based on silicon-on-insulator allow to develop optics and electronics functions on the same chip. Developments in this area are fostered by its potential as an I/O technology that can meet the throughputs demand of future many-core processors. Most of the optical interconnect designs rely on small footprint and high power efficiency microring resonators. They are used to filter out individual channels from a shared bus guide. Second-order microring filters enable denser channel packing by having sharper pass-band to stop-band slopes. Taking advantage of using a single physical ring with clockwise and counter-clockwise propagation, we implement second order filters with lower tuning energy consumption as being more resilient to some fabrication errors. Cascade ability, remote stabilization potential, energy efficiency along with simple design equations on coupling coefficients are described. We design second-order filters with FWHM from 45 GHz to 20 GHz, crosstalk between channels from -40 dB to -20 dB for different channel spacing at a specific FSR, with energy efficiencies of single ring configurations and compatible with silicon-on-insulator (SOI) state of the art platforms.