Acoustic one-way mode conversion and transmission by sonic crystal waveguides

TL;DR

This paper presents a novel acoustic waveguide system using sonic crystals that enables one-way mode conversion and transmission, functioning as an acoustic diode and mode converter.

Contribution

It introduces a scheme for unidirectional acoustic mode switching based on symmetry matching in sonic crystal waveguides with a resonant cavity.

Findings

Achieved one-way mode conversion in sonic crystal waveguides.

Demonstrated potential for acoustic diode applications.

Enabled mode switching between even and odd modes.

Abstract

We proposed a scheme to achieve one-way acoustic propagation and even odd mode switching in two mutually perpendicular sonic crystal waveguides connected by a resonant cavity. The even mode in the entrance waveguide is able to switch to odd mode in the exit waveguide through a symmetry match between the cavity resonant modes and the waveguide modes. Conversely, the odd mode in the exit waveguide is unable to be converted into the even mode in the entrance waveguide as incident waves and eigenmodes are mismatched in their symmetries at the waveguide exit. This one way mechanism can be applied to design an acoustic diode for acoustic integration devices and can be used as a convertor of the acoustic waveguide modes.