Multiband large-area ultrasonic energy conveying and harvesting via a phononic topological heterostructure

Abstract

Phononic topological insulators supporting robust mechanical wave localization hold great promise in ultrasonic energy conveying and harvesting (UECH) applications. However, prevailing topological devices for UECH suffer from typical bottlenecks, e.g., low energy capacity and singular operating frequency band, severely restricting the UECH performance in real-world application scenarios. To address these challenges, we herein develop a phononic topological heterostructure (PTH), which hosts large-area topological waveguide states within three frequency windows, for multiband and high-throughput ultrasonic energy transport. By integrating the PTH with piezoelectric transducers, the ultrasonic energies conveyed by the PTH are further converted into electric signals for energy harvesting applications. Our work suggests a promising way for multiband and high-throughput UECH, having the potential in improving communication capacities of micro-electromechanical systems and developing high-performance self-powered micro devices.