Algorithm-enhanced high-resolution silicon photonic spectrometer with micro-ring resonators

A high-resolution on-chip optical spectrometer is proposed and demonstrated with the performance enhancement by introducing a spectrum reconstruction algorithm. The present spectrometer consists of a high-Q Euler micro-racetrack resonator with an array of second-order adiabatic elliptical micro-rings, achieving a high resolution of ∼15 pm and a working window of ∼27 nm. With the algorithm, the spectrum analyzing becomes immune to the inter-channel crosstalk of the array of optical filters, and thus the signal-noise ratio is improved by 10 dB in comparison with the conventional spectrum analysis using direct measurement, greatly helping the realization of high-performance on-chip spectrometers in the future.