Energy-efficient power trimming for reliable nanophotonic NoC microring resonators

Microring resonators, one of the key components in nanophotonic networks-on-chip (NoCs), are highly sensitive to process and temperature variations. The consequential resonant wavelength deviations negatively impact reliable on-chip communication. To revert resonant wavelengths to their desired values and recover bandwidth, power trimming is usually applied; unfortunately, this technique incurs considerable energy overhead. In this work, we present an energy-efficient power trimming technique that considers the group shifting effect caused by temperature variations. Experimental results show that our approach improves energy-efficiency by up to 30% (with negligible ~ 3% bandwidth degradation), over the next best power trimming method.