Acoustic imaging and collimating by slabs of sonic crystals made from arrays of rigid cylinders in air

TL;DR

This paper explores how slabs of sonic crystals made from rigid cylinders can manipulate acoustic waves, demonstrating collimation, guiding, and imaging effects within specific bandgap frequencies.

Contribution

It reveals new properties of acoustic propagation in sonic crystals, including wave collimation, guidance, and stable imaging within partial bandgaps, extending understanding of wave control in these structures.

Findings

Waves are collimated or guided within partial bandgaps.

Stable acoustic imaging is achievable with flat sonic crystal slabs.

Band structure analysis explains wave propagation behaviors.

Abstract

We show some new properties of the acoustic propagation in two-dimensional sonic crystals, formed by parallel rigid cylinders placed in air. The transmission through slabs of sonic crystals and the associated band structures are considered. It is shown that within partial bandgaps, the waves tend to be collimated or guided into the direction in which the propagation is allowed. Such a feature also prevails in the situations in which deaf bands appear. We show that within the partial bandgaps, a stable imaging effect can be obtained for flat sonic crystal slabs, in analogy to the cases with photonic crystals.