Angle-dependent ultrasonic transmission through plates with subwavelength hole arrays

TL;DR

This paper investigates how sound transmits through perforated plates with subwavelength holes, revealing unique angle-dependent properties that differ from optical and slit-based acoustical transmission, and highlighting the role of resonances and modes.

Contribution

It demonstrates the distinctive acoustic transmission behaviors in perforated plates, emphasizing the influence of Wood anomalies and coupling with Lamb and Scholte-Stoneley modes, which is novel compared to prior optical and slit acoustics studies.

Findings

Transmission minima respond to Wood anomalies.

Homogeneous-plate modes strongly couple with resonances.

Unique angle-dependent transmission behaviors observed.

Abstract

We study sound transmission in perforated plates as a function of incident angle and conclude that it holds distinctive properties that make it unique and essentially different from optical transmission through perforated metallic plates. More precisely, we conclude the following: (a) similar to its optical counterpart, acoustic transmission minima respond to Wood anomalies in which the periodicity plays a central role; (b) in contrast to both the optical case and the acoustical case with slits, homogeneous-plate modes (Lamb and Scholte-Stoneley modes) are strongly coupled to lattice and Fabry-P\'erot resonances. This gives rise to unique transmission behavior, thus opening new perspectives for exotic wave phenomena.