Ultra-broadband acoustic logic gate based on passive phase manipulation

In recent years, acoustic logic gates has attracted growing interest in acoustics due to their promising applications in acoustic communication and signal processing. For practical implementation, these logic gates must operate over a certain bandwidth to ensure reliable performance. However, current experimental realizations have predominantly been confined to single-frequency or narrowband operation, leaving their broadband capabilities largely unverified. To address this gap, we present both numerical and experimental demonstrations of three basic acoustic logic gates (OR, NOT, and AND) using a phased unit cell composed of a central channel flanked by two arrays of semicircular cavities. By leveraging phase modulation of the unit cells and linear interference of sound, we achieve these logic operations with a uniform threshold of I_t = 0.25. Remarkably, the measured fractional bandwidths (bandwidth relative to center frequency) reach approximately 111.5% (OR), 37.2% (NOT), and 48.5% (AND), demonstrating ultra-broadband functionality. The proposed logic gates combine exceptional bandwidth with structural simplicity, offering significant potential for applications in acoustic computing, information processing, and integrated acoustic systems.