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 µm 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.