Acoustic soft metacollimator by broadband digital phase encoding

Abstract

<p>Phase engineering plays a pivotal role in various scientific research and industrial applications including microwaves, optics, and acoustics. However, traditional phase engineering methods lack the flexibility for arbitrary programming due to the absence of digitization. Conversely, while broadband digitization technology holds promise, its utilization in wave engineering has been constrained by narrowband transmission capabilities. In this study, we introduce a novel approach to broadband digital phase encoding spanning frequencies from 50 to 500 kHz. Our methodology is exemplified through the development of an acoustic soft metacollimator with simulations and experiments conducted underwater across different frequency ranges. Our findings demonstrate that the soft metacollimator significantly enhances transmission intensity by 7.7 dB and improves spatial resolution by a factor of 10. Moreover, the soft metacollimator enables novel functionalities such as long-distance energy enhancement and broadband coding properties in underwater acoustics. This pioneering broadband digital phase encoding technique holds promise for advancing next-generation phase engineering and offers versatile applications in biomedical ultrasonics, acoustic communications, and the development of underwater broadband acoustic antennas.<br></p>