An asymmetric generator of acoustic vortex with high-purity

Abstract

The asymmetric generation of acoustic vortex refers to the physical characteristics that pass the generated acoustic vortex in one direction while blocking it in the opposite direction. Such an effect has drawn much attention in acoustic vortex-based applications, but there is relatively little research about it. In this paper, we theoretically conceive an approach to realize asymmetric acoustic vortices with high purity by an asymmetric generator composed of a mode converter (MC) and a mode selector (MS). The underlying process is achieved with an integrated design combing vortex mode conversion and mode selection. The corresponding results of simulations and an experiment further confirmed the novel phenomenon. In addition, the designed configuration obtains unidirectional acoustic vortices with high purity, which may have potential in asymmetric acoustic communication.