Toward High-Speed And Energy-Efficient Computing: A Wdm-Based Scalable On-Chip Silicon Integrated Optical Comparator

Integrated photonics has shown extraordinary potential in optical computing. Various optical computing modules have been investigated, among which the digital comparator is a significant element for any arithmetic logic unit. In this study, an architecture of a wavelength-division-multiplexing-based (WDM-based) electronic-photonic digital comparator is proposed, which can perform high-bit comparisons for fixed-point or floating-point binary inputs. A silicon photonics-based 2-bit comparator operating at 20 Gb s(-1) at a 1.55 mu m wavelength is experimentally demonstrated. A detailed performance analysis reveals that this architecture outperforms the current transistor-based electronic comparators in terms of both computational speed and power efficiency.